cpp conversion: minimal steps to fix compilation errors, not warnings

204 files changed, 730 insertions, 707 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index f484acd8..990ca74d 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -15,20 +15,20 @@ include_HEADERS = proj.h proj_experimental.h proj_constants.h proj_api.h geodesi
 
 EXTRA_DIST = bin_cct.cmake bin_gie.cmake bin_cs2cs.cmake \
 	bin_geod.cmake bin_nad2bin.cmake bin_proj.cmake bin_projinfo.cmake \
-	lib_proj.cmake CMakeLists.txt bin_geodtest.cmake geodtest.c \
+	lib_proj.cmake CMakeLists.txt bin_geodtest.cmake geodtest.cpp \
 	pj_wkt1_grammar.y pj_wkt2_grammar.y
 
-proj_SOURCES = proj.c gen_cheb.c p_series.c
+proj_SOURCES = proj.cpp gen_cheb.cpp p_series.cpp
 projinfo_SOURCES = projinfo.cpp
-cs2cs_SOURCES = cs2cs.cpp gen_cheb.c p_series.c
-cct_SOURCES = cct.c proj_strtod.c proj_strtod.h optargpm.h
-nad2bin_SOURCES = nad2bin.c
-geod_SOURCES = geod.c geod_set.c geod_interface.c geod_interface.h
+cs2cs_SOURCES = cs2cs.cpp gen_cheb.cpp p_series.cpp
+cct_SOURCES = cct.cpp proj_strtod.cpp proj_strtod.h optargpm.h
+nad2bin_SOURCES = nad2bin.cpp
+geod_SOURCES = geod.cpp geod_set.cpp geod_interface.cpp geod_interface.h
 
-gie_SOURCES = gie.c proj_strtod.c proj_strtod.h optargpm.h
-multistresstest_SOURCES = multistresstest.c
-test228_SOURCES = test228.c
-geodtest_SOURCES = geodtest.c
+gie_SOURCES = gie.cpp proj_strtod.cpp proj_strtod.h optargpm.h
+multistresstest_SOURCES = multistresstest.cpp
+test228_SOURCES = test228.cpp
+geodtest_SOURCES = geodtest.cpp
 
 cct_LDADD = libproj.la
 cs2cs_LDADD = libproj.la
@@ -51,51 +51,51 @@ libproj_la_SOURCES = \
 	pj_list.h proj_internal.h proj_math.h projects.h\
 	static.cpp util.cpp metadata.cpp common.cpp crs.cpp datum.cpp coordinatesystem.cpp coordinateoperation.cpp io.cpp \
 	internal.cpp factory.cpp c_api.cpp \
-	PJ_aeqd.c PJ_gnom.c PJ_laea.c PJ_mod_ster.c \
-	PJ_nsper.c PJ_nzmg.c PJ_ortho.c PJ_stere.c PJ_sterea.c \
-	PJ_aea.c PJ_bipc.c PJ_bonne.c PJ_eqdc.c PJ_isea.c PJ_ccon.c\
-	PJ_imw_p.c PJ_krovak.c PJ_lcc.c PJ_poly.c \
-	PJ_rpoly.c PJ_sconics.c proj_rouss.c \
-	PJ_cass.c PJ_cc.c PJ_cea.c PJ_eqc.c PJ_gall.c PJ_geoc.c \
-	PJ_labrd.c PJ_lsat.c PJ_misrsom.c PJ_merc.c \
-	PJ_mill.c PJ_ocea.c PJ_omerc.c PJ_somerc.c \
-	PJ_tcc.c PJ_tcea.c PJ_times.c PJ_tmerc.c PJ_tobmerc.c \
-	PJ_airy.c PJ_aitoff.c PJ_august.c PJ_bacon.c \
-	PJ_bertin1953.c PJ_chamb.c PJ_hammer.c PJ_lagrng.c PJ_larr.c \
-	PJ_lask.c PJ_latlong.c PJ_nocol.c PJ_ob_tran.c PJ_oea.c \
-	PJ_tpeqd.c PJ_vandg.c PJ_vandg2.c PJ_vandg4.c \
-	PJ_wag7.c PJ_lcca.c PJ_geos.c proj_etmerc.c \
-	PJ_boggs.c PJ_collg.c PJ_comill.c PJ_crast.c PJ_denoy.c \
-	PJ_eck1.c PJ_eck2.c PJ_eck3.c PJ_eck4.c \
-	PJ_eck5.c PJ_fahey.c PJ_fouc_s.c PJ_gins8.c PJ_gstmerc.c \
-	PJ_gn_sinu.c PJ_goode.c PJ_igh.c PJ_hatano.c PJ_loxim.c \
-	PJ_mbt_fps.c PJ_mbtfpp.c PJ_mbtfpq.c PJ_moll.c \
-	PJ_nell.c PJ_nell_h.c PJ_patterson.c PJ_putp2.c PJ_putp3.c \
-	PJ_putp4p.c PJ_putp5.c PJ_putp6.c PJ_qsc.c PJ_robin.c \
-	PJ_sch.c PJ_sts.c PJ_urm5.c PJ_urmfps.c PJ_wag2.c \
-	PJ_wag3.c PJ_wink1.c PJ_wink2.c pj_geocent.c \
-	aasincos.c adjlon.c bch2bps.c bchgen.c \
-	biveval.c dmstor.c mk_cheby.c pj_auth.c \
-	pj_deriv.c pj_ell_set.c pj_ellps.c pj_errno.c \
-	pj_factors.c pj_fwd.c pj_init.c pj_inv.c \
-	pj_list.c pj_malloc.c pj_mlfn.c pj_msfn.c proj_mdist.c \
-	pj_open_lib.c pj_param.c pj_phi2.c pj_pr_list.c \
-	pj_qsfn.c pj_strerrno.c \
-	pj_tsfn.c pj_units.c pj_ctx.c pj_log.c pj_zpoly1.c rtodms.c \
-	vector1.c pj_release.c pj_gauss.c \
-	PJ_healpix.c PJ_natearth.c PJ_natearth2.c PJ_calcofi.c pj_fileapi.c \
-	PJ_eqearth.c \
+	PJ_aeqd.cpp PJ_gnom.cpp PJ_laea.cpp PJ_mod_ster.cpp \
+	PJ_nsper.cpp PJ_nzmg.cpp PJ_ortho.cpp PJ_stere.cpp PJ_sterea.cpp \
+	PJ_aea.cpp PJ_bipc.cpp PJ_bonne.cpp PJ_eqdc.cpp PJ_isea.cpp PJ_ccon.cpp \
+	PJ_imw_p.cpp PJ_krovak.cpp PJ_lcc.cpp PJ_poly.cpp \
+	PJ_rpoly.cpp PJ_sconics.cpp proj_rouss.cpp \
+	PJ_cass.cpp PJ_cc.cpp PJ_cea.cpp PJ_eqc.cpp PJ_gall.cpp PJ_geoc.cpp \
+	PJ_labrd.cpp PJ_lsat.cpp PJ_misrsom.cpp PJ_merc.cpp \
+	PJ_mill.cpp PJ_ocea.cpp PJ_omerc.cpp PJ_somerc.cpp \
+	PJ_tcc.cpp PJ_tcea.cpp PJ_times.cpp PJ_tmerc.cpp PJ_tobmerc.cpp \
+	PJ_airy.cpp PJ_aitoff.cpp PJ_august.cpp PJ_bacon.cpp \
+	PJ_bertin1953.cpp PJ_chamb.cpp PJ_hammer.cpp PJ_lagrng.cpp PJ_larr.cpp \
+	PJ_lask.cpp PJ_latlong.cpp PJ_nocol.cpp PJ_ob_tran.cpp PJ_oea.cpp \
+	PJ_tpeqd.cpp PJ_vandg.cpp PJ_vandg2.cpp PJ_vandg4.cpp \
+	PJ_wag7.cpp PJ_lcca.cpp PJ_geos.cpp proj_etmerc.cpp \
+	PJ_boggs.cpp PJ_collg.cpp PJ_comill.cpp PJ_crast.cpp PJ_denoy.cpp \
+	PJ_eck1.cpp PJ_eck2.cpp PJ_eck3.cpp PJ_eck4.cpp \
+	PJ_eck5.cpp PJ_fahey.cpp PJ_fouc_s.cpp PJ_gins8.cpp PJ_gstmerc.cpp \
+	PJ_gn_sinu.cpp PJ_goode.cpp PJ_igh.cpp PJ_hatano.cpp PJ_loxim.cpp \
+	PJ_mbt_fps.cpp PJ_mbtfpp.cpp PJ_mbtfpq.cpp PJ_moll.cpp \
+	PJ_nell.cpp PJ_nell_h.cpp PJ_patterson.cpp PJ_putp2.cpp PJ_putp3.cpp \
+	PJ_putp4p.cpp PJ_putp5.cpp PJ_putp6.cpp PJ_qsc.cpp PJ_robin.cpp \
+	PJ_sch.cpp PJ_sts.cpp PJ_urm5.cpp PJ_urmfps.cpp PJ_wag2.cpp \
+	PJ_wag3.cpp PJ_wink1.cpp PJ_wink2.cpp pj_geocent.cpp \
+	aasincos.cpp adjlon.cpp bch2bps.cpp bchgen.cpp \
+	biveval.cpp dmstor.cpp mk_cheby.cpp pj_auth.cpp \
+	pj_deriv.cpp pj_ell_set.cpp pj_ellps.cpp pj_errno.cpp \
+	pj_factors.cpp pj_fwd.cpp pj_init.cpp pj_inv.cpp \
+	pj_list.cpp pj_malloc.cpp pj_mlfn.cpp pj_msfn.cpp proj_mdist.cpp \
+	pj_open_lib.cpp pj_param.cpp pj_phi2.cpp pj_pr_list.cpp \
+	pj_qsfn.cpp pj_strerrno.cpp \
+	pj_tsfn.cpp pj_units.cpp pj_ctx.cpp pj_log.cpp pj_zpoly1.cpp rtodms.cpp \
+	vector1.cpp pj_release.cpp pj_gauss.cpp \
+	PJ_healpix.cpp PJ_natearth.cpp PJ_natearth2.cpp PJ_calcofi.cpp pj_fileapi.cpp \
+	PJ_eqearth.cpp \
 	\
-	pj_gc_reader.c pj_gridcatalog.c \
-	nad_cvt.c nad_init.c nad_intr.c emess.c emess.h \
-	pj_apply_gridshift.c pj_datums.c pj_datum_set.c pj_transform.c \
-	geocent.c geocent.h pj_utils.c pj_gridinfo.c pj_gridlist.c \
-	jniproj.c pj_mutex.c pj_initcache.c pj_apply_vgridshift.c geodesic.c \
-	pj_strtod.c pj_math.c\
+	pj_gc_reader.cpp pj_gridcatalog.cpp \
+	nad_cvt.cpp nad_init.cpp nad_intr.cpp emess.cpp emess.h \
+	pj_apply_gridshift.cpp pj_datums.cpp pj_datum_set.cpp pj_transform.cpp \
+	geocent.cpp geocent.h pj_utils.cpp pj_gridinfo.cpp pj_gridlist.cpp \
+	jniproj.cpp pj_mutex.cpp pj_initcache.cpp pj_apply_vgridshift.cpp geodesic.cpp \
+	pj_strtod.cpp pj_math.cpp \
 	\
-	proj_4D_api.c PJ_cart.c PJ_pipeline.c PJ_horner.c PJ_helmert.c \
-	PJ_vgridshift.c PJ_hgridshift.c PJ_unitconvert.c PJ_molodensky.c \
-	PJ_deformation.c pj_internal.c PJ_axisswap.c PJ_affine.c \
+	proj_4D_api.cpp PJ_cart.cpp PJ_pipeline.cpp PJ_horner.cpp PJ_helmert.cpp \
+	PJ_vgridshift.cpp PJ_hgridshift.cpp PJ_unitconvert.cpp PJ_molodensky.cpp \
+	PJ_deformation.cpp pj_internal.cpp PJ_axisswap.cpp PJ_affine.cpp \
 	pj_wkt_parser.hpp pj_wkt_parser.cpp \
 	pj_wkt1_parser.h pj_wkt1_parser.cpp \
 	pj_wkt1_generated_parser.h pj_wkt1_generated_parser.c \
diff --git a/src/PJ_aea.c b/src/PJ_aea.cpp
index 640f1013..e4d1dc4f 100644
--- a/src/PJ_aea.c
+++ b/src/PJ_aea.cpp
@@ -82,14 +82,14 @@ struct pj_opaque {
 };
 
 
-static void *destructor (PJ *P, int errlev) {                        /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
@@ -99,7 +99,7 @@ static void *destructor (PJ *P, int errlev) {                        /* Destruct
 
 static XY e_forward (LP lp, PJ *P) {   /* Ellipsoid/spheroid, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     Q->rho = Q->c - (Q->ellips ? Q->n * pj_qsfn(sin(lp.phi), P->e, P->one_es) : Q->n2 * sin(lp.phi));;
     if (Q->rho < 0.) {
         proj_errno_set(P, PJD_ERR_TOLERANCE_CONDITION);
@@ -114,7 +114,7 @@ static XY e_forward (LP lp, PJ *P) {   /* Ellipsoid/spheroid, forward */
 
 static LP e_inverse (XY xy, PJ *P) {   /* Ellipsoid/spheroid, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     if( (Q->rho = hypot(xy.x, xy.y = Q->rho0 - xy.y)) != 0.0 ) {
         if (Q->n < 0.) {
             Q->rho = -Q->rho;
@@ -148,7 +148,7 @@ static LP e_inverse (XY xy, PJ *P) {   /* Ellipsoid/spheroid, inverse */
 static PJ *setup(PJ *P) {
     double cosphi, sinphi;
     int secant;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     P->inv = e_inverse;
     P->fwd = e_forward;
@@ -196,7 +196,7 @@ static PJ *setup(PJ *P) {
 
 
 PJ *PROJECTION(aea) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -209,7 +209,7 @@ PJ *PROJECTION(aea) {
 
 
 PJ *PROJECTION(leac) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_aeqd.c b/src/PJ_aeqd.cpp
index 5d8c3d38..72c7ae95 100644
--- a/src/PJ_aeqd.c
+++ b/src/PJ_aeqd.cpp
@@ -58,14 +58,14 @@ PROJ_HEAD(aeqd, "Azimuthal Equidistant") "\n\tAzi, Sph&Ell\n\tlat_0 guam";
 #define TOL 1.e-14
 
 
-static void *destructor (PJ *P, int errlev) {                        /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
@@ -73,7 +73,7 @@ static void *destructor (PJ *P, int errlev) {                        /* Destruct
 
 static XY e_guam_fwd(LP lp, PJ *P) {        /* Guam elliptical */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  cosphi, sinphi, t;
 
     cosphi = cos(lp.phi);
@@ -89,7 +89,7 @@ static XY e_guam_fwd(LP lp, PJ *P) {        /* Guam elliptical */
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  coslam, cosphi, sinphi, rho;
     double azi1, azi2, s12;
     double lam1, phi1, lam2, phi2;
@@ -128,7 +128,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  coslam, cosphi, sinphi;
 
     sinphi = sin(lp.phi);
@@ -175,7 +175,7 @@ oblcon:
 
 static LP e_guam_inv(XY xy, PJ *P) { /* Guam elliptical */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double x2, t = 0.0;
     int i;
 
@@ -193,7 +193,7 @@ static LP e_guam_inv(XY xy, PJ *P) { /* Guam elliptical */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double c;
     double azi1, azi2, s12, x2, y2, lat1, lon1, lat2, lon2;
 
@@ -225,7 +225,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cosc, c_rh, sinc;
 
     if ((c_rh = hypot(xy.x, xy.y)) > M_PI) {
@@ -265,7 +265,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(aeqd) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_affine.c b/src/PJ_affine.cpp
index 0d8b6374..b8fa4c68 100644
--- a/src/PJ_affine.c
+++ b/src/PJ_affine.cpp
@@ -107,7 +107,7 @@ static LP reverse_2d(XY xy, PJ *P) {
 }
 
 static struct pj_opaque_affine * initQ() {
-    struct pj_opaque_affine *Q = pj_calloc(1, sizeof(struct pj_opaque_affine));
+    struct pj_opaque_affine *Q = static_cast<struct pj_opaque_affine *>(pj_calloc(1, sizeof(struct pj_opaque_affine)));
     if (0==Q)
         return 0;
 
diff --git a/src/PJ_airy.c b/src/PJ_airy.cpp
index 75f95780..037362b3 100644
--- a/src/PJ_airy.c
+++ b/src/PJ_airy.cpp
@@ -56,7 +56,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  sinlam, coslam, cosphi, sinphi, t, s, Krho, cosz;
 
     sinlam = sin(lp.lam);
@@ -111,7 +111,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 PJ *PROJECTION(airy) {
     double beta;
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
 
diff --git a/src/PJ_aitoff.c b/src/PJ_aitoff.cpp
index 82c981d5..1af75469 100644
--- a/src/PJ_aitoff.c
+++ b/src/PJ_aitoff.cpp
@@ -60,7 +60,7 @@ FORWARD(s_forward); /* spheroid */
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double c, d;
 
     if((d = acos(cos(lp.phi) * cos(c = 0.5 * lp.lam))) != 0.0) {/* basic Aitoff */
@@ -98,7 +98,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     int iter, MAXITER = 10, round = 0, MAXROUND = 20;
     double EPSILON = 1e-12, D, C, f1, f2, f1p, f1l, f2p, f2l, dp, dl, sl, sp, cp, cl, x, y;
 
@@ -170,7 +170,7 @@ static PJ *setup(PJ *P) {
 
 
 PJ *PROJECTION(aitoff) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
@@ -181,7 +181,7 @@ PJ *PROJECTION(aitoff) {
 
 
 PJ *PROJECTION(wintri) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_august.c b/src/PJ_august.cpp
index e891e84e..e891e84e 100644
--- a/src/PJ_august.c
+++ b/src/PJ_august.cpp
diff --git a/src/PJ_axisswap.c b/src/PJ_axisswap.cpp
index 6db4a7d2..d21eddb1 100644
--- a/src/PJ_axisswap.c
+++ b/src/PJ_axisswap.cpp
@@ -161,7 +161,7 @@ static PJ_COORD reverse_4d(PJ_COORD coo, PJ *P) {
 /***********************************************************************/
 PJ *CONVERSION(axisswap,0) {
 /***********************************************************************/
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     char *s;
     unsigned int i, j, n = 0;
 
diff --git a/src/PJ_bacon.c b/src/PJ_bacon.cpp
index f0f11c9d..f995e420 100644
--- a/src/PJ_bacon.c
+++ b/src/PJ_bacon.cpp
@@ -19,7 +19,7 @@ PROJ_HEAD(bacon, "Bacon Globular") "\n\tMisc Sph, no inv";
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 	double ax, f;
 
 	xy.y = Q->bacn ? M_HALFPI * sin(lp.phi) : lp.phi;
@@ -39,7 +39,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 
 PJ *PROJECTION(bacon) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -53,7 +53,7 @@ PJ *PROJECTION(bacon) {
 
 
 PJ *PROJECTION(apian) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -66,7 +66,7 @@ PJ *PROJECTION(apian) {
 
 
 PJ *PROJECTION(ortel) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_bertin1953.c b/src/PJ_bertin1953.cpp
index 5a027da2..46420314 100644
--- a/src/PJ_bertin1953.c
+++ b/src/PJ_bertin1953.cpp
@@ -28,7 +28,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     double fu = 1.4, k = 12., w = 1.68, d;
 
@@ -74,7 +74,7 @@ static XY s_forward (LP lp, PJ *P) {
 
 
 PJ *PROJECTION(bertin1953) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_bipc.c b/src/PJ_bipc.cpp
index e4a69077..243ecccd 100644
--- a/src/PJ_bipc.c
+++ b/src/PJ_bipc.cpp
@@ -36,7 +36,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cphi, sphi, tphi, t, al, Az, z, Av, cdlam, sdlam, r;
     int tag;
 
@@ -113,7 +113,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double t, r, rp, rl, al, z = 0.0, fAz, Az, s, c, Av;
     int neg, i;
 
@@ -161,7 +161,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(bipc) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_boggs.c b/src/PJ_boggs.cpp
index 119357c0..119357c0 100644
--- a/src/PJ_boggs.c
+++ b/src/PJ_boggs.cpp
diff --git a/src/PJ_bonne.c b/src/PJ_bonne.cpp
index d3d5b757..6c51af7c 100644
--- a/src/PJ_bonne.c
+++ b/src/PJ_bonne.cpp
@@ -20,7 +20,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double rh, E, c;
 
     rh = Q->am1 + Q->m1 - pj_mlfn(lp.phi, E = sin(lp.phi), c = cos(lp.phi), Q->en);
@@ -33,7 +33,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double E, rh;
 
     rh = Q->cphi1 + Q->phi1 - lp.phi;
@@ -48,7 +48,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double rh;
 
     rh = hypot(xy.x, xy.y = Q->cphi1 - xy.y);
@@ -67,7 +67,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double s, rh;
 
     rh = hypot(xy.x, xy.y = Q->am1 - xy.y);
@@ -87,21 +87,21 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 
 
-static void *destructor (PJ *P, int errlev) {                        /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
 
 PJ *PROJECTION(bonne) {
     double c;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_calcofi.c b/src/PJ_calcofi.cpp
index ed4cfe86..ed4cfe86 100644
--- a/src/PJ_calcofi.c
+++ b/src/PJ_calcofi.cpp
diff --git a/src/PJ_cart.c b/src/PJ_cart.cpp
index 6fed9985..6fed9985 100644
--- a/src/PJ_cart.c
+++ b/src/PJ_cart.cpp
diff --git a/src/PJ_cass.c b/src/PJ_cass.cpp
index 4e3b4251..cc610940 100644
--- a/src/PJ_cass.c
+++ b/src/PJ_cass.cpp
@@ -25,7 +25,7 @@ struct pj_opaque {
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     double n, t, a1, c, a2, tn;
     XY xy = {0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     xy.y = pj_mlfn (lp.phi, n = sin (lp.phi), c = cos (lp.phi), Q->en);
 
@@ -55,7 +55,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     double n, t, r, dd, d2, tn, ph1;
     LP lp = {0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     ph1 = pj_inv_mlfn (P->ctx, Q->m0 + xy.y, P->es, Q->en);
     tn  = tan (ph1); t = tn*tn;
@@ -81,14 +81,14 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     return lp;
 }
 
-static void *destructor (PJ *P, int errlev) {                        /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
@@ -104,16 +104,16 @@ PJ *PROJECTION(cass) {
     }
 
     /* otherwise it's ellipsoidal */
-    P->opaque = pj_calloc (1, sizeof (struct pj_opaque));
+    P->opaque = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==P->opaque)
         return pj_default_destructor (P, ENOMEM);
     P->destructor = destructor;
 
-    P->opaque->en = pj_enfn (P->es);
-    if (0==P->opaque->en)
+    static_cast<struct pj_opaque*>(P->opaque)->en = pj_enfn (P->es);
+    if (0==static_cast<struct pj_opaque*>(P->opaque)->en)
         return pj_default_destructor (P, ENOMEM);
 
-    P->opaque->m0 = pj_mlfn (P->phi0,  sin (P->phi0),  cos (P->phi0),  P->opaque->en);
+    static_cast<struct pj_opaque*>(P->opaque)->m0 = pj_mlfn (P->phi0,  sin (P->phi0),  cos (P->phi0),  static_cast<struct pj_opaque*>(P->opaque)->en);
     P->inv = e_inverse;
     P->fwd = e_forward;
 
diff --git a/src/PJ_cc.c b/src/PJ_cc.cpp
index 152e6e4a..152e6e4a 100644
--- a/src/PJ_cc.c
+++ b/src/PJ_cc.cpp
diff --git a/src/PJ_ccon.c b/src/PJ_ccon.cpp
index 0b8b70cb..6ff2d3b1 100644
--- a/src/PJ_ccon.c
+++ b/src/PJ_ccon.cpp
@@ -43,7 +43,7 @@ PROJ_HEAD(ccon, "Central Conic")
 
 static XY forward (LP lp, PJ *P) {
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double r;
 
     r = Q->ctgphi1 - tan(lp.phi - Q->phi1);
@@ -56,7 +56,7 @@ static XY forward (LP lp, PJ *P) {
 
 static LP inverse (XY xy, PJ *P) {
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     xy.y = Q->ctgphi1 - xy.y;
     lp.phi = Q->phi1 - atan(hypot(xy.x,xy.y) - Q->ctgphi1);
@@ -66,21 +66,21 @@ static LP inverse (XY xy, PJ *P) {
 }
 
 
-static void *destructor (PJ *P, int errlev) {
+static PJ *destructor (PJ *P, int errlev) {
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
 
 PJ *PROJECTION(ccon) {
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_cea.c b/src/PJ_cea.cpp
index e05e524b..ee7eebf5 100644
--- a/src/PJ_cea.c
+++ b/src/PJ_cea.cpp
@@ -33,7 +33,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    lp.phi = pj_authlat(asin( 2. * xy.y * P->k0 / P->opaque->qp), P->opaque->apa);
+    lp.phi = pj_authlat(asin( 2. * xy.y * P->k0 / static_cast<struct pj_opaque*>(P->opaque)->qp), static_cast<struct pj_opaque*>(P->opaque)->apa);
     lp.lam = xy.x / P->k0;
     return lp;
 }
@@ -56,21 +56,21 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     return (lp);
 }
 
-static void *destructor (PJ *P, int errlev) {                        /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->apa);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->apa);
     return pj_default_destructor (P, errlev);
 }
 
 
 PJ *PROJECTION(cea) {
     double t = 0.0;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_chamb.c b/src/PJ_chamb.cpp
index 6951d6a1..8d8f05ee 100644
--- a/src/PJ_chamb.c
+++ b/src/PJ_chamb.cpp
@@ -54,7 +54,7 @@ static double lc(projCtx ctx, double b,double c,double a) {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double sinphi, cosphi, a;
     VECT v[3];
     int i, j;
@@ -101,7 +101,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 PJ *PROJECTION(chamb) {
     int i, j;
     char line[10];
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_collg.c b/src/PJ_collg.cpp
index 7904de29..7904de29 100644
--- a/src/PJ_collg.c
+++ b/src/PJ_collg.cpp
diff --git a/src/PJ_comill.c b/src/PJ_comill.cpp
index b6e0192e..b6e0192e 100644
--- a/src/PJ_comill.c
+++ b/src/PJ_comill.cpp
diff --git a/src/PJ_crast.c b/src/PJ_crast.cpp
index 4e4dee8b..4e4dee8b 100644
--- a/src/PJ_crast.c
+++ b/src/PJ_crast.cpp
diff --git a/src/PJ_deformation.c b/src/PJ_deformation.cpp
index 5511eed4..1398f5fd 100644
--- a/src/PJ_deformation.c
+++ b/src/PJ_deformation.cpp
@@ -86,7 +86,7 @@ static XYZ get_grid_shift(PJ* P, XYZ cartesian) {
     int previous_errno = proj_errno_reset(P);
 
     /* cartesian to geodetic */
-    geodetic.lpz = pj_inv3d(cartesian, P->opaque->cart);
+    geodetic.lpz = pj_inv3d(cartesian, static_cast<struct pj_opaque*>(P->opaque)->cart);
 
     /* look up correction values in grids */
     shift.lp    = proj_hgrid_value(P, geodetic.lp);
@@ -245,15 +245,15 @@ static PJ_COORD reverse_4d(PJ_COORD in, PJ *P) {
     return out;
 }
 
-static void *destructor(PJ *P, int errlev) {
+static PJ *destructor(PJ *P, int errlev) {
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    if (P->opaque->cart)
-        P->opaque->cart->destructor (P->opaque->cart, errlev);
+    if (static_cast<struct pj_opaque*>(P->opaque)->cart)
+        static_cast<struct pj_opaque*>(P->opaque)->cart->destructor (static_cast<struct pj_opaque*>(P->opaque)->cart, errlev);
 
     return pj_default_destructor(P, errlev);
 }
@@ -262,7 +262,7 @@ static void *destructor(PJ *P, int errlev) {
 PJ *TRANSFORMATION(deformation,1) {
     int has_xy_grids = 0;
     int has_z_grids  = 0;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return destructor(P, ENOMEM);
     P->opaque = (void *) Q;
diff --git a/src/PJ_denoy.c b/src/PJ_denoy.cpp
index 5c337c45..5c337c45 100644
--- a/src/PJ_denoy.c
+++ b/src/PJ_denoy.cpp
diff --git a/src/PJ_eck1.c b/src/PJ_eck1.cpp
index 88a7430c..88a7430c 100644
--- a/src/PJ_eck1.c
+++ b/src/PJ_eck1.cpp
diff --git a/src/PJ_eck2.c b/src/PJ_eck2.cpp
index f76ab4ec..f76ab4ec 100644
--- a/src/PJ_eck2.c
+++ b/src/PJ_eck2.cpp
diff --git a/src/PJ_eck3.c b/src/PJ_eck3.cpp
index 8f91c8bb..7993d781 100644
--- a/src/PJ_eck3.c
+++ b/src/PJ_eck3.cpp
@@ -17,7 +17,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     xy.y = Q->C_y * lp.phi;
     xy.x = Q->C_x * lp.lam * (Q->A + asqrt(1. - Q->B * lp.phi * lp.phi));
@@ -27,7 +27,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double denominator;
 
     lp.phi = xy.y / Q->C_y;
@@ -49,7 +49,7 @@ static PJ *setup(PJ *P) {
 
 
 PJ *PROJECTION(eck3) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -64,7 +64,7 @@ PJ *PROJECTION(eck3) {
 
 
 PJ *PROJECTION(kav7) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -82,7 +82,7 @@ PJ *PROJECTION(kav7) {
 
 
 PJ *PROJECTION(wag6) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -96,7 +96,7 @@ PJ *PROJECTION(wag6) {
 
 
 PJ *PROJECTION(putp1) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_eck4.c b/src/PJ_eck4.cpp
index 4fa4c21f..4fa4c21f 100644
--- a/src/PJ_eck4.c
+++ b/src/PJ_eck4.cpp
diff --git a/src/PJ_eck5.c b/src/PJ_eck5.cpp
index f9f28460..f9f28460 100644
--- a/src/PJ_eck5.c
+++ b/src/PJ_eck5.cpp
diff --git a/src/PJ_eqc.c b/src/PJ_eqc.cpp
index 07d6141c..b95471f7 100644
--- a/src/PJ_eqc.c
+++ b/src/PJ_eqc.cpp
@@ -16,7 +16,7 @@ PROJ_HEAD(eqc, "Equidistant Cylindrical (Plate Carree)")
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     xy.x = Q->rc * lp.lam;
     xy.y = lp.phi - P->phi0;
@@ -27,7 +27,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     lp.lam = xy.x / Q->rc;
     lp.phi = xy.y + P->phi0;
@@ -37,7 +37,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(eqc) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_eqdc.c b/src/PJ_eqdc.cpp
index 8caca87a..468b16df 100644
--- a/src/PJ_eqdc.c
+++ b/src/PJ_eqdc.cpp
@@ -25,7 +25,7 @@ PROJ_HEAD(eqdc, "Equidistant Conic")
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     Q->rho = Q->c - (Q->ellips ? pj_mlfn(lp.phi, sin(lp.phi),
         cos(lp.phi), Q->en) : lp.phi);
@@ -38,7 +38,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     if ((Q->rho = hypot(xy.x, xy.y = Q->rho0 - xy.y)) != 0.0 ) {
         if (Q->n < 0.) {
@@ -58,14 +58,14 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 }
 
 
-static void *destructor (PJ *P, int errlev) {                        /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
@@ -74,7 +74,7 @@ PJ *PROJECTION(eqdc) {
     double cosphi, sinphi;
     int secant;
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_eqearth.c b/src/PJ_eqearth.cpp
index a0d4467b..34d85fa5 100644
--- a/src/PJ_eqearth.c
+++ b/src/PJ_eqearth.cpp
@@ -39,7 +39,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {           /* Ellipsoidal/spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double sbeta;
     double psi, psi2, psi6;
 
@@ -73,7 +73,7 @@ static XY e_forward (LP lp, PJ *P) {           /* Ellipsoidal/spheroidal, forwar
 
 static LP e_inverse (XY xy, PJ *P) {           /* Ellipsoidal/spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double yc, y2, y6;
     int i;
 
@@ -127,20 +127,20 @@ static LP e_inverse (XY xy, PJ *P) {           /* Ellipsoidal/spheroidal, invers
     return lp;
 }
 
-static void *destructor (PJ *P, int errlev) { /* Destructor */
+static PJ *destructor (PJ *P, int errlev) { /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->apa);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->apa);
     return pj_default_destructor (P, errlev);
 }
 
 
 PJ *PROJECTION(eqearth) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_fahey.c b/src/PJ_fahey.cpp
index 85e0ab69..85e0ab69 100644
--- a/src/PJ_fahey.c
+++ b/src/PJ_fahey.cpp
diff --git a/src/PJ_fouc_s.c b/src/PJ_fouc_s.cpp
index 6efe34bd..8c223336 100644
--- a/src/PJ_fouc_s.c
+++ b/src/PJ_fouc_s.cpp
@@ -18,7 +18,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double t;
 
     t = cos(lp.phi);
@@ -30,7 +30,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double V;
     int i;
 
@@ -53,7 +53,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(fouc_s) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_gall.c b/src/PJ_gall.cpp
index a8697482..a8697482 100644
--- a/src/PJ_gall.c
+++ b/src/PJ_gall.cpp
diff --git a/src/PJ_geoc.c b/src/PJ_geoc.cpp
index 0455fada..0455fada 100644
--- a/src/PJ_geoc.c
+++ b/src/PJ_geoc.cpp
diff --git a/src/PJ_geos.c b/src/PJ_geos.cpp
index 0eb25610..ffe0771c 100644
--- a/src/PJ_geos.c
+++ b/src/PJ_geos.cpp
@@ -52,7 +52,7 @@ PROJ_HEAD(geos, "Geostationary Satellite View") "\n\tAzi, Sph&Ell\n\th=";
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double Vx, Vy, Vz, tmp;
 
     /* Calculation of the three components of the vector from satellite to
@@ -82,7 +82,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double r, Vx, Vy, Vz, tmp;
 
     /* Calculation of geocentric latitude. */
@@ -118,7 +118,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double Vx, Vy, Vz, a, b, det, k;
 
     /* Setting three components of vector from satellite to position.*/
@@ -155,7 +155,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double Vx, Vy, Vz, a, b, det, k;
 
     /* Setting three components of vector from satellite to position.*/
@@ -195,7 +195,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 PJ *PROJECTION(geos) {
     char *sweep_axis;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_gins8.c b/src/PJ_gins8.cpp
index c1a2fff0..c1a2fff0 100644
--- a/src/PJ_gins8.c
+++ b/src/PJ_gins8.cpp
diff --git a/src/PJ_gn_sinu.c b/src/PJ_gn_sinu.cpp
index 2ef0f263..2c7824ac 100644
--- a/src/PJ_gn_sinu.c
+++ b/src/PJ_gn_sinu.cpp
@@ -25,7 +25,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
     double s, c;
 
-    xy.y = pj_mlfn(lp.phi, s = sin(lp.phi), c = cos(lp.phi), P->opaque->en);
+    xy.y = pj_mlfn(lp.phi, s = sin(lp.phi), c = cos(lp.phi), static_cast<struct pj_opaque*>(P->opaque)->en);
     xy.x = lp.lam * c / sqrt(1. - P->es * s * s);
     return xy;
 }
@@ -35,7 +35,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
     double s;
 
-    if ((s = fabs(lp.phi = pj_inv_mlfn(P->ctx, xy.y, P->es, P->opaque->en))) < M_HALFPI) {
+    if ((s = fabs(lp.phi = pj_inv_mlfn(P->ctx, xy.y, P->es, static_cast<struct pj_opaque*>(P->opaque)->en))) < M_HALFPI) {
         s = sin(lp.phi);
         lp.lam = xy.x * sqrt(1. - P->es * s * s) / cos(lp.phi);
     } else if ((s - EPS10) < M_HALFPI) {
@@ -50,7 +50,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     if (Q->m == 0.0)
         lp.phi = Q->n != 1. ? aasin(P->ctx,Q->n * sin(lp.phi)): lp.phi;
@@ -80,7 +80,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     xy.y /= Q->C_y;
     lp.phi = (Q->m != 0.0) ? aasin(P->ctx,(Q->m * xy.y + sin(xy.y)) / Q->n) :
@@ -90,14 +90,14 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 }
 
 
-static void *destructor (PJ *P, int errlev) {                        /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
@@ -105,7 +105,7 @@ static void *destructor (PJ *P, int errlev) {                        /* Destruct
 
 /* for spheres, only */
 static void setup(PJ *P) {
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     P->es = 0;
     P->inv = s_inverse;
     P->fwd = s_forward;
@@ -115,7 +115,7 @@ static void setup(PJ *P) {
 
 
 PJ *PROJECTION(sinu) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -137,7 +137,7 @@ PJ *PROJECTION(sinu) {
 
 
 PJ *PROJECTION(eck6) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -152,7 +152,7 @@ PJ *PROJECTION(eck6) {
 
 
 PJ *PROJECTION(mbtfps) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -167,7 +167,7 @@ PJ *PROJECTION(mbtfps) {
 
 
 PJ *PROJECTION(gn_sinu) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_gnom.c b/src/PJ_gnom.cpp
index 635ae49e..7313643f 100644
--- a/src/PJ_gnom.c
+++ b/src/PJ_gnom.cpp
@@ -27,7 +27,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  coslam, cosphi, sinphi;
 
     sinphi = sin(lp.phi);
@@ -75,7 +75,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  rh, cosz, sinz;
 
     rh = hypot(xy.x, xy.y);
@@ -120,7 +120,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(gnom) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_goode.c b/src/PJ_goode.cpp
index 8d8ac24d..3f5a4f8c 100644
--- a/src/PJ_goode.c
+++ b/src/PJ_goode.cpp
@@ -21,7 +21,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     if (fabs(lp.phi) <= PHI_LIM)
         xy = Q->sinu->fwd(lp, Q->sinu);
@@ -35,7 +35,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     if (fabs(xy.y) <= PHI_LIM)
         lp = Q->sinu->inv(xy, Q->sinu);
@@ -47,20 +47,20 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 }
 
 
-static void *destructor (PJ *P, int errlev) {              /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {              /* Destructor */
     if (0==P)
         return 0;
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
-    pj_free (P->opaque->sinu);
-    pj_free (P->opaque->moll);
+    pj_free (static_cast<struct pj_opaque*>(P->opaque)->sinu);
+    pj_free (static_cast<struct pj_opaque*>(P->opaque)->moll);
     return pj_default_destructor (P, errlev);
 }
 
 
 
 PJ *PROJECTION(goode) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_gstmerc.c b/src/PJ_gstmerc.cpp
index 5b5109b0..6475f972 100644
--- a/src/PJ_gstmerc.c
+++ b/src/PJ_gstmerc.cpp
@@ -21,7 +21,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double L, Ls, sinLs1, Ls1;
 
     L = Q->n1*lp.lam;
@@ -37,7 +37,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double L, LC, sinC;
 
     L = atan(sinh((xy.x * P->a - Q->XS) / Q->n2) / cos((xy.y * P->a - Q->YS) / Q->n2));
@@ -51,7 +51,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(gstmerc) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_hammer.c b/src/PJ_hammer.cpp
index f3e0d64e..474d44ca 100644
--- a/src/PJ_hammer.c
+++ b/src/PJ_hammer.cpp
@@ -19,7 +19,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cosphi, d;
 
     d = sqrt(2./(1. + (cosphi = cos(lp.phi)) * cos(lp.lam *= Q->w)));
@@ -31,7 +31,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double z;
 
     z = sqrt(1. - 0.25*Q->w*Q->w*xy.x*xy.x - 0.25*xy.y*xy.y);
@@ -48,7 +48,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(hammer) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_hatano.c b/src/PJ_hatano.cpp
index 019671cc..019671cc 100644
--- a/src/PJ_hatano.c
+++ b/src/PJ_hatano.cpp
diff --git a/src/PJ_healpix.c b/src/PJ_healpix.cpp
index 3a88695f..a7d42398 100644
--- a/src/PJ_healpix.c
+++ b/src/PJ_healpix.cpp
@@ -229,7 +229,7 @@ static int in_image(double x, double y, int proj, int north_square,
  * P contains the relevant ellipsoid parameters.
  **/
 static double auth_lat(PJ *P, double alpha, int inverse) {
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     if (inverse == 0) {
         /* Authalic latitude. */
         double q = pj_qsfn(sin(alpha), P->e, 1.0 - P->es);
@@ -366,13 +366,13 @@ static CapMap get_cap(double x, double y, int north_square, int south_square,
     capmap.y = y;
     if (inverse == 0) {
         if (y > M_FORTPI) {
-            capmap.region = north;
+            capmap.region = CapMap::north;
             c = M_HALFPI;
         } else if (y < -M_FORTPI) {
-            capmap.region = south;
+            capmap.region = CapMap::south;
             c = -M_HALFPI;
         } else {
-            capmap.region = equatorial;
+            capmap.region = CapMap::equatorial;
             capmap.cn = 0;
             return capmap;
         }
@@ -396,23 +396,23 @@ static CapMap get_cap(double x, double y, int north_square, int south_square,
         }
     } else {
         if (y > M_FORTPI) {
-            capmap.region = north;
+            capmap.region = CapMap::north;
             capmap.x = -3*M_FORTPI + north_square*M_HALFPI;
             capmap.y = M_HALFPI;
             x = x - north_square*M_HALFPI;
         } else if (y < -M_FORTPI) {
-            capmap.region = south;
+            capmap.region = CapMap::south;
             capmap.x = -3*M_FORTPI + south_square*M_HALFPI;
             capmap.y = -M_HALFPI;
             x = x - south_square*M_HALFPI;
         } else {
-            capmap.region = equatorial;
+            capmap.region = CapMap::equatorial;
             capmap.cn = 0;
             return capmap;
         }
         /* Polar Region, find the HEALPix polar cap number that
            x, y moves to when rHEALPix polar square is disassembled. */
-        if (capmap.region == north) {
+        if (capmap.region == CapMap::north) {
             if (y >= -x - M_FORTPI - EPS && y < x + 5*M_FORTPI - EPS) {
                 capmap.cn = (north_square + 1) % 4;
             } else if (y > -x -M_FORTPI + EPS && y >= x + 5*M_FORTPI - EPS) {
@@ -422,7 +422,7 @@ static CapMap get_cap(double x, double y, int north_square, int south_square,
             } else {
                 capmap.cn = north_square;
             }
-        } else if (capmap.region == south) {
+        } else if (capmap.region == CapMap::south) {
             if (y <= x + M_FORTPI + EPS && y > -x - 5*M_FORTPI + EPS) {
                 capmap.cn = (south_square + 1) % 4;
             } else if (y < x + M_FORTPI - EPS && y <= -x - 5*M_FORTPI + EPS) {
@@ -459,7 +459,7 @@ static XY combine_caps(double x, double y, int north_square, int south_square,
     int pole = 0;
 
     CapMap capmap = get_cap(x, y, north_square, south_square, inverse);
-    if (capmap.region == equatorial) {
+    if (capmap.region == CapMap::equatorial) {
         xy.x = capmap.x;
         xy.y = capmap.y;
         return xy;
@@ -472,7 +472,7 @@ static XY combine_caps(double x, double y, int north_square, int south_square,
         /* Rotate (x, y) about its polar cap tip and then translate it to
            north_square or south_square. */
 
-        if (capmap.region == north) {
+        if (capmap.region == CapMap::north) {
             pole = north_square;
             tmpRot = rot[get_rotate_index(capmap.cn - pole)];
         } else {
@@ -484,7 +484,7 @@ static XY combine_caps(double x, double y, int north_square, int south_square,
          Unrotate (x, y) and then translate it back. */
 
         /* disassemble */
-        if (capmap.region == north) {
+        if (capmap.region == CapMap::north) {
             pole = north_square;
             tmpRot = rot[get_rotate_index(-1*(capmap.cn - pole))];
         } else {
@@ -500,7 +500,7 @@ static XY combine_caps(double x, double y, int north_square, int south_square,
         /* Workaround cppcheck git issue */
         double* pa = a;
         pa[0] = -3*M_FORTPI + ((inverse == 0) ? pole : capmap.cn) *M_HALFPI;
-        pa[1] = ((capmap.region == north) ? 1 : -1) *M_HALFPI;
+        pa[1] = ((capmap.region == CapMap::north) ? 1 : -1) *M_HALFPI;
         vector_add(ret_dot, a, vector);
     }
 
@@ -552,7 +552,7 @@ static LP e_healpix_inverse(XY xy, PJ *P) { /* ellipsoid */
 
 
 static XY s_rhealpix_forward(LP lp, PJ *P) { /* sphere */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     XY xy = healpix_sphere(lp);
     return combine_caps(xy.x, xy.y, Q->north_square, Q->south_square, 0);
@@ -560,7 +560,7 @@ static XY s_rhealpix_forward(LP lp, PJ *P) { /* sphere */
 
 
 static XY e_rhealpix_forward(LP lp, PJ *P) { /* ellipsoid */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     XY xy;
     lp.phi = auth_lat(P, lp.phi, 0);
     xy = healpix_sphere(lp);
@@ -569,7 +569,7 @@ static XY e_rhealpix_forward(LP lp, PJ *P) { /* ellipsoid */
 
 
 static LP s_rhealpix_inverse(XY xy, PJ *P) { /* sphere */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     /* Check whether (x, y) lies in the rHEALPix image. */
     if (in_image(xy.x, xy.y, 1, Q->north_square, Q->south_square) == 0) {
@@ -585,7 +585,7 @@ static LP s_rhealpix_inverse(XY xy, PJ *P) { /* sphere */
 
 
 static LP e_rhealpix_inverse(XY xy, PJ *P) { /* ellipsoid */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     LP lp = {0.0,0.0};
 
     /* Check whether (x, y) lies in the rHEALPix image. */
@@ -602,20 +602,20 @@ static LP e_rhealpix_inverse(XY xy, PJ *P) { /* ellipsoid */
 }
 
 
-static void *destructor (PJ *P, int errlev) {                        /* Destructor */
+static PJ *destructor (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->apa);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->apa);
     return pj_default_destructor (P, errlev);
 }
 
 
 PJ *PROJECTION(healpix) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -640,7 +640,7 @@ PJ *PROJECTION(healpix) {
 
 
 PJ *PROJECTION(rhealpix) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_helmert.c b/src/PJ_helmert.cpp
index 757cf950..c19422cb 100644
--- a/src/PJ_helmert.c
+++ b/src/PJ_helmert.cpp
@@ -476,7 +476,7 @@ static PJ_COORD helmert_reverse_4d (PJ_COORD point, PJ *P) {
 
 
 static PJ* init_helmert_six_parameters(PJ* P) {
-    struct pj_opaque_helmert *Q = pj_calloc (1, sizeof (struct pj_opaque_helmert));
+    struct pj_opaque_helmert *Q = static_cast<struct pj_opaque_helmert*>(pj_calloc (1, sizeof (struct pj_opaque_helmert)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = (void *) Q;
diff --git a/src/PJ_hgridshift.c b/src/PJ_hgridshift.cpp
index 2919a85c..86c6cdee 100644
--- a/src/PJ_hgridshift.c
+++ b/src/PJ_hgridshift.cpp
@@ -79,7 +79,7 @@ static PJ_COORD reverse_4d(PJ_COORD obs, PJ *P) {
 
 
 PJ *TRANSFORMATION(hgridshift,0) {
-    struct pj_opaque_hgridshift *Q = pj_calloc (1, sizeof (struct pj_opaque_hgridshift));
+    struct pj_opaque_hgridshift *Q = static_cast<struct pj_opaque_hgridshift*>(pj_calloc (1, sizeof (struct pj_opaque_hgridshift)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = (void *) Q;
diff --git a/src/PJ_horner.c b/src/PJ_horner.cpp
index a6a26e52..49e108c8 100644
--- a/src/PJ_horner.c
+++ b/src/PJ_horner.cpp
@@ -141,7 +141,7 @@ static HORNER *horner_alloc (size_t order, int complex_polynomia) {
     /* size_t is unsigned, so we need not check for order > 0 */
     int n = (int)horner_number_of_coefficients(order);
     int polynomia_ok = 0;
-    HORNER *h = horner_calloc (1, sizeof (HORNER));
+    HORNER *h = static_cast<HORNER*>(horner_calloc (1, sizeof (HORNER)));
 
     if (0==h)
         return 0;
@@ -152,22 +152,22 @@ static HORNER *horner_alloc (size_t order, int complex_polynomia) {
     h->coefs = n;
 
     if (complex_polynomia) {
-        h->fwd_c = horner_calloc (n, sizeof(double));
-        h->inv_c = horner_calloc (n, sizeof(double));
+        h->fwd_c = static_cast<double*>(horner_calloc (n, sizeof(double)));
+        h->inv_c = static_cast<double*>(horner_calloc (n, sizeof(double)));
         if (h->fwd_c && h->inv_c)
             polynomia_ok = 1;
     }
     else {
-        h->fwd_u = horner_calloc (n, sizeof(double));
-        h->fwd_v = horner_calloc (n, sizeof(double));
-        h->inv_u = horner_calloc (n, sizeof(double));
-        h->inv_v = horner_calloc (n, sizeof(double));
+        h->fwd_u = static_cast<double*>(horner_calloc (n, sizeof(double)));
+        h->fwd_v = static_cast<double*>(horner_calloc (n, sizeof(double)));
+        h->inv_u = static_cast<double*>(horner_calloc (n, sizeof(double)));
+        h->inv_v = static_cast<double*>(horner_calloc (n, sizeof(double)));
         if (h->fwd_u && h->fwd_v && h->inv_u && h->inv_v)
             polynomia_ok = 1;
     }
 
-    h->fwd_origin = horner_calloc (1, sizeof(UV));
-    h->inv_origin = horner_calloc (1, sizeof(UV));
+    h->fwd_origin = static_cast<UV*>(horner_calloc (1, sizeof(UV)));
+    h->inv_origin = static_cast<UV*>(horner_calloc (1, sizeof(UV)));
 
     if (polynomia_ok && h->fwd_origin && h->inv_origin)
         return h;
@@ -297,12 +297,12 @@ summing the tiny high order elements first.
 
 
 static PJ_COORD horner_forward_4d (PJ_COORD point, PJ *P) {
-    point.uv = horner ((HORNER *) P->opaque, 1, point.uv);
+    point.uv = horner ((HORNER *) P->opaque, PJ_FWD, point.uv);
     return point;
 }
 
 static PJ_COORD horner_reverse_4d (PJ_COORD point, PJ *P) {
-    point.uv = horner ((HORNER *) P->opaque, -1, point.uv);
+    point.uv = horner ((HORNER *) P->opaque, PJ_INV, point.uv);
     return point;
 }
 
@@ -397,7 +397,7 @@ static PJ_COORD complex_horner_reverse_4d (PJ_COORD point, PJ *P) {
 }
 
 
-static void *horner_freeup (PJ *P, int errlev) {                        /* Destructor */
+static PJ *horner_freeup (PJ *P, int errlev) {                        /* Destructor */
     if (0==P)
         return 0;
     if (0==P->opaque)
@@ -412,7 +412,7 @@ static int parse_coefs (PJ *P, double *coefs, char *param, int ncoefs) {
     char *buf, *init, *next = 0;
     int i;
 
-    buf = pj_calloc (strlen (param) + 2, sizeof(char));
+    buf = static_cast<char*>(pj_calloc (strlen (param) + 2, sizeof(char)));
     if (0==buf) {
         proj_log_error (P, "Horner: No memory left");
         return 0;
@@ -474,7 +474,7 @@ PJ *PROJECTION(horner) {
     Q = horner_alloc (degree, complex_polynomia);
     if (Q == 0)
         return horner_freeup (P, ENOMEM);
-    P->opaque = (void *) Q;
+    P->opaque = Q;
 
     if (complex_polynomia) {
         /* Westings and/or southings? */
diff --git a/src/PJ_igh.c b/src/PJ_igh.cpp
index c991649a..476d1c6b 100644
--- a/src/PJ_igh.c
+++ b/src/PJ_igh.cpp
@@ -40,7 +40,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     int z;
 
     if (lp.phi >=  d4044118) {          /* 1|2 */
@@ -73,7 +73,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     const double y90 = Q->dy0 + sqrt(2); /* lt=90 corresponds to y=y0+sqrt(2) */
 
     int z = 0;
@@ -134,7 +134,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 }
 
 
-static void *destructor (PJ *P, int errlev) {
+static PJ *destructor (PJ *P, int errlev) {
     int i;
     if (0==P)
         return 0;
@@ -143,8 +143,8 @@ static void *destructor (PJ *P, int errlev) {
         return pj_default_destructor (P, errlev);
 
     for (i = 0; i < 12; ++i) {
-        if (P->opaque->pj[i])
-            P->opaque->pj[i]->destructor(P->opaque->pj[i], errlev);
+        if (static_cast<struct pj_opaque*>(P->opaque)->pj[i])
+            static_cast<struct pj_opaque*>(P->opaque)->pj[i]->destructor(static_cast<struct pj_opaque*>(P->opaque)->pj[i], errlev);
     }
 
     return pj_default_destructor(P, errlev);
@@ -184,7 +184,7 @@ static void *destructor (PJ *P, int errlev) {
 PJ *PROJECTION(igh) {
     XY xy1, xy3;
     LP lp = { 0, d4044118 };
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_imw_p.c b/src/PJ_imw_p.cpp
index abed5006..7bf9405a 100644
--- a/src/PJ_imw_p.c
+++ b/src/PJ_imw_p.cpp
@@ -27,7 +27,7 @@ struct pj_opaque {
 
 
 static int phi12(PJ *P, double *del, double *sig) {
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     int err = 0;
 
     if (!pj_param(P->ctx, P->params, "tlat_1").i ||
@@ -45,7 +45,7 @@ static int phi12(PJ *P, double *del, double *sig) {
 
 
 static XY loc_for(LP lp, PJ *P, double *yc) {
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     XY xy;
 
     if (lp.phi == 0.0) {
@@ -102,7 +102,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     XY t;
     double yc = 0.0;
     int i = 0;
@@ -132,21 +132,21 @@ static void xy(PJ *P, double phi, double *x, double *y, double *sp, double *R) {
 
     *sp = sin(phi);
     *R = 1./(tan(phi) * sqrt(1. - P->es * *sp * *sp ));
-    F = P->opaque->lam_1 * *sp;
+    F = static_cast<struct pj_opaque*>(P->opaque)->lam_1 * *sp;
     *y = *R * (1 - cos(F));
     *x = *R * sin(F);
 }
 
 
-static void *destructor (PJ *P, int errlev) {
+static PJ *destructor (PJ *P, int errlev) {
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    if( P->opaque->en )
-        pj_dealloc (P->opaque->en);
+    if( static_cast<struct pj_opaque*>(P->opaque)->en )
+        pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
 
     return pj_default_destructor(P, errlev);
 }
@@ -155,7 +155,7 @@ static void *destructor (PJ *P, int errlev) {
 PJ *PROJECTION(imw_p) {
     double del, sig, s, t, x1, x2, T2, y1, m1, m2, y2;
     int err;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_isea.c b/src/PJ_isea.cpp
index 4ffd2983..6170b8a1 100644
--- a/src/PJ_isea.c
+++ b/src/PJ_isea.cpp
@@ -981,7 +981,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     struct isea_pt out;
     struct isea_geo in;
 
@@ -999,7 +999,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 PJ *PROJECTION(isea) {
     char *opt;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_krovak.c b/src/PJ_krovak.cpp
index 5ca21214..7e0488f0 100644
--- a/src/PJ_krovak.c
+++ b/src/PJ_krovak.cpp
@@ -101,7 +101,7 @@ struct pj_opaque {
 
 
 static XY e_forward (LP lp, PJ *P) {                /* Ellipsoidal, forward */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     XY xy = {0.0,0.0};
 
     double gfi, u, deltav, s, d, eps, rho;
@@ -128,7 +128,7 @@ static XY e_forward (LP lp, PJ *P) {                /* Ellipsoidal, forward */
 
 
 static LP e_inverse (XY xy, PJ *P) {                /* Ellipsoidal, inverse */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     LP lp = {0.0,0.0};
 
     double u, deltav, s, d, eps, rho, fi1, xy0;
@@ -176,7 +176,7 @@ static LP e_inverse (XY xy, PJ *P) {                /* Ellipsoidal, inverse */
 
 PJ *PROJECTION(krovak) {
     double u0, n0, g;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_labrd.c b/src/PJ_labrd.cpp
index 769dc620..e40bbcbd 100644
--- a/src/PJ_labrd.c
+++ b/src/PJ_labrd.cpp
@@ -15,7 +15,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double V1, V2, ps, sinps, cosps, sinps2, cosps2;
     double I1, I2, I3, I4, I5, I6, x2, y2, t;
 
@@ -48,7 +48,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     /* t = 0.0 optimization is to avoid a false positive cppcheck warning */
     /* (cppcheck git beaf29c15867984aa3c2a15cf15bd7576ccde2b3). Might no */
     /* longer be necessary with later versions. */
@@ -100,7 +100,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 PJ *PROJECTION(labrd) {
     double Az, sinp, R, N, t;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_laea.c b/src/PJ_laea.cpp
index bcf9c44d..02b34858 100644
--- a/src/PJ_laea.c
+++ b/src/PJ_laea.cpp
@@ -30,7 +30,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double coslam, sinlam, sinphi, q, sinb=0.0, cosb=0.0, b=0.0;
 
     coslam = cos(lp.lam);
@@ -92,7 +92,7 @@ eqcon:
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  coslam, cosphi, sinphi;
 
     sinphi = sin(lp.phi);
@@ -134,7 +134,7 @@ oblcon:
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cCe, sCe, q, rho, ab=0.0;
 
     switch (Q->mode) {
@@ -183,7 +183,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  cosz=0.0, rh, sinz=0.0;
 
     rh = hypot(xy.x, xy.y);
@@ -222,14 +222,14 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 }
 
 
-static void *destructor (PJ *P, int errlev) {
+static PJ *destructor (PJ *P, int errlev) {
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->apa);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->apa);
 
     return pj_default_destructor(P, errlev);
 }
@@ -237,7 +237,7 @@ static void *destructor (PJ *P, int errlev) {
 
 PJ *PROJECTION(laea) {
     double t;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_lagrng.c b/src/PJ_lagrng.cpp
index 3856fcdc..f5363287 100644
--- a/src/PJ_lagrng.c
+++ b/src/PJ_lagrng.cpp
@@ -21,7 +21,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double v, c;
 
     if (fabs(fabs(lp.phi) - M_HALFPI) < TOL) {
@@ -45,7 +45,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double c, x2, y2p, y2m;
 
     if (fabs(fabs(xy.y) - 2.) < TOL) {
@@ -69,7 +69,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 PJ *PROJECTION(lagrng) {
     double phi1;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_larr.c b/src/PJ_larr.cpp
index e4d5d240..e4d5d240 100644
--- a/src/PJ_larr.c
+++ b/src/PJ_larr.cpp
diff --git a/src/PJ_lask.c b/src/PJ_lask.cpp
index 46f23edb..46f23edb 100644
--- a/src/PJ_lask.c
+++ b/src/PJ_lask.cpp
diff --git a/src/PJ_latlong.c b/src/PJ_latlong.cpp
index 1331d59a..1331d59a 100644
--- a/src/PJ_latlong.c
+++ b/src/PJ_latlong.cpp
diff --git a/src/PJ_lcc.c b/src/PJ_lcc.cpp
index 96aa3f2a..5c430ea0 100644
--- a/src/PJ_lcc.c
+++ b/src/PJ_lcc.cpp
@@ -20,7 +20,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0., 0.};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double rho;
 
     if (fabs(fabs(lp.phi) - M_HALFPI) < EPS10) {
@@ -43,7 +43,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0., 0.};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double rho;
 
     xy.x /= P->k0;
@@ -78,7 +78,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 PJ *PROJECTION(lcc) {
     double cosphi, sinphi;
     int secant;
-    struct pj_opaque *Q = pj_calloc(1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc(1, sizeof (struct pj_opaque)));
 
     if (0 == Q)
         return pj_default_destructor(P, ENOMEM);
diff --git a/src/PJ_lcca.c b/src/PJ_lcca.cpp
index f0f256b1..cbb18709 100644
--- a/src/PJ_lcca.c
+++ b/src/PJ_lcca.cpp
@@ -80,7 +80,7 @@ static double fSp(double S, double C) {       /* deriv of fs */
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double S, r, dr;
 
     S = pj_mlfn(lp.phi, sin(lp.phi), cos(lp.phi), Q->en) - Q->M0;
@@ -94,7 +94,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double theta, dr, S, dif;
     int i;
 
@@ -118,21 +118,21 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 }
 
 
-static void *destructor (PJ *P, int errlev) {
+static PJ *destructor (PJ *P, int errlev) {
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
 
 PJ *PROJECTION(lcca) {
     double s2p0, N0, R0, tan0;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_loxim.c b/src/PJ_loxim.cpp
index 512bfc23..28e955d9 100644
--- a/src/PJ_loxim.c
+++ b/src/PJ_loxim.cpp
@@ -19,7 +19,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     xy.y = lp.phi - Q->phi1;
     if (fabs(xy.y) < EPS)
@@ -37,7 +37,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     lp.phi = xy.y + Q->phi1;
     if (fabs(xy.y) < EPS) {
@@ -54,7 +54,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(loxim) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_lsat.c b/src/PJ_lsat.cpp
index 810a1cba..e3e7e026 100644
--- a/src/PJ_lsat.c
+++ b/src/PJ_lsat.cpp
@@ -18,7 +18,7 @@ struct pj_opaque {
 };
 
 static void seraz0(double lam, double mult, PJ *P) {
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double sdsq, h, s, fc, sd, sq, d__1 = 0;
 
     lam *= DEG_TO_RAD;
@@ -44,7 +44,7 @@ static void seraz0(double lam, double mult, PJ *P) {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     int l, nn;
     double lamt = 0.0, xlam, sdsq, c, d, s, lamdp = 0.0, phidp, lampp, tanph;
     double lamtp, cl, sd, sp, sav, tanphi;
@@ -107,7 +107,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     int nn;
     double lamt, sdsq, s, lamdp, phidp, sppsq, dd, sd, sl, fac, scl, sav, spp;
 
@@ -153,7 +153,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 PJ *PROJECTION(lsat) {
     int land, path;
     double lam, alf, esc, ess;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_mbt_fps.c b/src/PJ_mbt_fps.cpp
index 66ed9458..66ed9458 100644
--- a/src/PJ_mbt_fps.c
+++ b/src/PJ_mbt_fps.cpp
diff --git a/src/PJ_mbtfpp.c b/src/PJ_mbtfpp.cpp
index 276a43eb..276a43eb 100644
--- a/src/PJ_mbtfpp.c
+++ b/src/PJ_mbtfpp.cpp
diff --git a/src/PJ_mbtfpq.c b/src/PJ_mbtfpq.cpp
index b7c0eb16..b7c0eb16 100644
--- a/src/PJ_mbtfpq.c
+++ b/src/PJ_mbtfpq.cpp
diff --git a/src/PJ_merc.c b/src/PJ_merc.cpp
index 1998234e..1998234e 100644
--- a/src/PJ_merc.c
+++ b/src/PJ_merc.cpp
diff --git a/src/PJ_mill.c b/src/PJ_mill.cpp
index 3ea9636f..3ea9636f 100644
--- a/src/PJ_mill.c
+++ b/src/PJ_mill.cpp
diff --git a/src/PJ_misrsom.c b/src/PJ_misrsom.cpp
index 0308fc42..537172c1 100644
--- a/src/PJ_misrsom.c
+++ b/src/PJ_misrsom.cpp
@@ -39,7 +39,7 @@ struct pj_opaque {
 };
 
 static void seraz0(double lam, double mult, PJ *P) {
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double sdsq, h, s, fc, sd, sq, d__1;
 
     lam *= DEG_TO_RAD;
@@ -62,7 +62,7 @@ static void seraz0(double lam, double mult, PJ *P) {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     int l, nn;
     double lamt = 0.0, xlam, sdsq, c, d, s, lamdp = 0.0, phidp, lampp, tanph;
     double lamtp, cl, sd, sp, sav, tanphi;
@@ -123,7 +123,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     int nn;
     double lamt, sdsq, s, lamdp, phidp, sppsq, dd, sd, sl, fac, scl, sav, spp;
 
@@ -170,7 +170,7 @@ PJ *PROJECTION(misrsom) {
     int path;
     double lam, alf, esc, ess;
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_mod_ster.c b/src/PJ_mod_ster.cpp
index 5e6ce136..ad5c9cdb 100644
--- a/src/PJ_mod_ster.c
+++ b/src/PJ_mod_ster.cpp
@@ -21,7 +21,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double sinlon, coslon, esphi, chi, schi, cchi, s;
     COMPLEX p;
 
@@ -45,7 +45,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     int nn;
     COMPLEX p, fxy, fpxy, dp;
     double den, rh = 0.0, z, sinz = 0.0, cosz = 0.0, chi, phi = 0.0, esphi;
@@ -101,7 +101,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 
 static PJ *setup(PJ *P) { /* general initialization */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double esphi, chio;
 
     if (P->es != 0.0) {
@@ -127,7 +127,7 @@ PJ *PROJECTION(mil_os) {
         {0.019430, 0.}
     };
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -150,7 +150,7 @@ PJ *PROJECTION(lee_os) {
         {-0.0088162, -0.00617325}
     };
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -175,7 +175,7 @@ PJ *PROJECTION(gs48) {
         {0.075528,  0.}
     };
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -210,7 +210,7 @@ PJ *PROJECTION(alsk) {
         { .3660976, -.2937382}
     };
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -258,7 +258,7 @@ PJ *PROJECTION(gs50) {
         {-.0225161,  .0853673}
     };
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_moll.c b/src/PJ_moll.cpp
index 4ac73841..ed7e946d 100644
--- a/src/PJ_moll.c
+++ b/src/PJ_moll.cpp
@@ -19,7 +19,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double k, V;
     int i;
 
@@ -42,7 +42,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     lp.phi = aasin(P->ctx, xy.y / Q->C_y);
     lp.lam = xy.x / (Q->C_x * cos(lp.phi));
         if (fabs(lp.lam) < M_PI) {
@@ -56,7 +56,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 static PJ * setup(PJ *P, double p) {
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double r, sp, p2 = p + p;
 
     P->es = 0;
@@ -74,7 +74,7 @@ static PJ * setup(PJ *P, double p) {
 
 
 PJ *PROJECTION(moll) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -84,7 +84,7 @@ PJ *PROJECTION(moll) {
 
 
 PJ *PROJECTION(wag4) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -93,7 +93,7 @@ PJ *PROJECTION(wag4) {
 }
 
 PJ *PROJECTION(wag5) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_molodensky.c b/src/PJ_molodensky.cpp
index dbc83768..6b231081 100644
--- a/src/PJ_molodensky.c
+++ b/src/PJ_molodensky.cpp
@@ -273,7 +273,7 @@ static PJ_COORD reverse_4d(PJ_COORD obs, PJ *P) {
 
 PJ *TRANSFORMATION(molodensky,1) {
     int count_required_params = 0;
-    struct pj_opaque_molodensky *Q = pj_calloc(1, sizeof(struct pj_opaque_molodensky));
+    struct pj_opaque_molodensky *Q = static_cast<struct pj_opaque_molodensky*>(pj_calloc(1, sizeof(struct pj_opaque_molodensky)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = (void *) Q;
diff --git a/src/PJ_natearth.c b/src/PJ_natearth.cpp
index 27a6b137..27a6b137 100644
--- a/src/PJ_natearth.c
+++ b/src/PJ_natearth.cpp
diff --git a/src/PJ_natearth2.c b/src/PJ_natearth2.cpp
index f6aba671..f6aba671 100644
--- a/src/PJ_natearth2.c
+++ b/src/PJ_natearth2.cpp
diff --git a/src/PJ_nell.c b/src/PJ_nell.cpp
index 2a7ea32c..2a7ea32c 100644
--- a/src/PJ_nell.c
+++ b/src/PJ_nell.cpp
diff --git a/src/PJ_nell_h.c b/src/PJ_nell_h.cpp
index 28c3ace7..28c3ace7 100644
--- a/src/PJ_nell_h.c
+++ b/src/PJ_nell_h.cpp
diff --git a/src/PJ_nocol.c b/src/PJ_nocol.cpp
index 541d08b2..541d08b2 100644
--- a/src/PJ_nocol.c
+++ b/src/PJ_nocol.cpp
diff --git a/src/PJ_nsper.c b/src/PJ_nsper.cpp
index 223cd75b..e6ecb852 100644
--- a/src/PJ_nsper.c
+++ b/src/PJ_nsper.cpp
@@ -36,7 +36,7 @@ PROJ_HEAD(tpers, "Tilted perspective") "\n\tAzi, Sph\n\ttilt= azi= h=";
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  coslam, cosphi, sinphi;
 
     sinphi = sin(lp.phi);
@@ -91,7 +91,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  rh, cosz, sinz;
 
     if (Q->tilt) {
@@ -140,7 +140,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 static PJ *setup(PJ *P) {
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     if ((Q->height = pj_param(P->ctx, P->params, "dh").f) <= 0.)
         return pj_default_destructor(P, PJD_ERR_H_LESS_THAN_ZERO);
@@ -168,7 +168,7 @@ static PJ *setup(PJ *P) {
 
 
 PJ *PROJECTION(nsper) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -182,7 +182,7 @@ PJ *PROJECTION(nsper) {
 PJ *PROJECTION(tpers) {
     double omega, gamma;
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_nzmg.c b/src/PJ_nzmg.cpp
index bf0862fb..bf0862fb 100644
--- a/src/PJ_nzmg.c
+++ b/src/PJ_nzmg.cpp
diff --git a/src/PJ_ob_tran.c b/src/PJ_ob_tran.cpp
index f5a05cf9..1a9417b8 100644
--- a/src/PJ_ob_tran.c
+++ b/src/PJ_ob_tran.cpp
@@ -23,7 +23,7 @@ PROJ_HEAD(ob_tran, "General Oblique Transformation") "\n\tMisc Sph"
 
 
 static XY o_forward(LP lp, PJ *P) {             /* spheroid */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double coslam, sinphi, cosphi;
 
     coslam = cos(lp.lam);
@@ -38,7 +38,7 @@ static XY o_forward(LP lp, PJ *P) {             /* spheroid */
 
 
 static XY t_forward(LP lp, PJ *P) {             /* spheroid */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cosphi, coslam;
 
     cosphi = cos(lp.phi);
@@ -52,7 +52,7 @@ static XY t_forward(LP lp, PJ *P) {             /* spheroid */
 
 static LP o_inverse(XY xy, PJ *P) {             /* spheroid */
 
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double coslam, sinphi, cosphi;
 
     LP lp = Q->link->inv(xy, Q->link);
@@ -70,7 +70,7 @@ static LP o_inverse(XY xy, PJ *P) {             /* spheroid */
 
 static LP t_inverse(XY xy, PJ *P) {             /* spheroid */
 
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cosphi, t;
 
     LP lp = Q->link->inv(xy, Q->link);
@@ -84,14 +84,14 @@ static LP t_inverse(XY xy, PJ *P) {             /* spheroid */
 }
 
 
-static void *destructor(PJ *P, int errlev) {
+static PJ *destructor(PJ *P, int errlev) {
     if (0==P)
         return 0;
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    if (P->opaque->link)
-        P->opaque->link->destructor (P->opaque->link, errlev);
+    if (static_cast<struct pj_opaque*>(P->opaque)->link)
+        static_cast<struct pj_opaque*>(P->opaque)->link->destructor (static_cast<struct pj_opaque*>(P->opaque)->link, errlev);
 
     return pj_default_destructor(P, errlev);
 }
@@ -135,7 +135,7 @@ static ARGS ob_tran_target_params (paralist *params) {
         return args;
 
     /* all args except the proj_ob_tran */
-    args.argv = pj_calloc (argc - 1, sizeof (char *));
+    args.argv = static_cast<char**>(pj_calloc (argc - 1, sizeof (char *)));
     if (0==args.argv)
         return args;
 
@@ -166,7 +166,7 @@ PJ *PROJECTION(ob_tran) {
     ARGS args;
     PJ *R; /* projection to rotate */
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return destructor(P, ENOMEM);
 
diff --git a/src/PJ_ocea.c b/src/PJ_ocea.cpp
index 7a9353a6..81c506fe 100644
--- a/src/PJ_ocea.c
+++ b/src/PJ_ocea.cpp
@@ -20,7 +20,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double t;
     xy.y = sin(lp.lam);
     t = cos(lp.lam);
@@ -35,7 +35,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double t, s;
 
     xy.y /= Q->rok;
@@ -51,7 +51,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 PJ *PROJECTION(ocea) {
     double phi_0=0.0, phi_1, phi_2, lam_1, lam_2, lonz, alpha;
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_oea.c b/src/PJ_oea.cpp
index 2bfeffa8..b39e8d5a 100644
--- a/src/PJ_oea.c
+++ b/src/PJ_oea.cpp
@@ -16,7 +16,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double Az, M, N, cp, sp, cl, shz;
 
     cp = cos(lp.phi);
@@ -35,7 +35,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double N, M, xp, yp, z, Az, cz, sz, cAz;
 
     N = Q->hn * aasin(P->ctx,xy.y * Q->rn);
@@ -57,7 +57,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(oea) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_omerc.c b/src/PJ_omerc.cpp
index 70c12e27..27b65cc7 100644
--- a/src/PJ_omerc.c
+++ b/src/PJ_omerc.cpp
@@ -45,7 +45,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double S, T, U, V, W, temp, u, v;
 
     if (fabs(fabs(lp.phi) - M_HALFPI) > EPS) {
@@ -84,7 +84,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  u, v, Qp, Sp, Tp, Vp, Up;
 
     if (Q->no_rot) {
@@ -120,7 +120,7 @@ PJ *PROJECTION(omerc) {
         gamma0, lamc=0, lam1=0, lam2=0, phi1=0, phi2=0, alpha_c=0;
     int alp, gam, no_off = 0;
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_ortho.c b/src/PJ_ortho.cpp
index d442aa8a..0e3641c0 100644
--- a/src/PJ_ortho.c
+++ b/src/PJ_ortho.cpp
@@ -31,7 +31,7 @@ static XY forward_error(PJ *P, LP lp, XY xy) {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  coslam, cosphi, sinphi;
 
     xy.x = HUGE_VAL; xy.y = HUGE_VAL;
@@ -65,7 +65,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  rh, cosc, sinc;
 
     lp.lam = HUGE_VAL; lp.phi = HUGE_VAL;
@@ -117,7 +117,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(ortho) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_patterson.c b/src/PJ_patterson.cpp
index 0d19414e..0d19414e 100644
--- a/src/PJ_patterson.c
+++ b/src/PJ_patterson.cpp
diff --git a/src/PJ_pipeline.c b/src/PJ_pipeline.cpp
index 618d4688..c20454df 100644
--- a/src/PJ_pipeline.c
+++ b/src/PJ_pipeline.cpp
@@ -132,10 +132,10 @@ static PJ_COORD pipeline_forward_4d (PJ_COORD point, PJ *P) {
     int i, first_step, last_step;
 
     first_step = 1;
-    last_step  = P->opaque->steps + 1;
+    last_step  = static_cast<struct pj_opaque*>(P->opaque)->steps + 1;
 
     for (i = first_step;  i != last_step;  i++)
-        point = proj_trans (P->opaque->pipeline[i], 1, point);
+        point = proj_trans (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i], PJ_FWD, point);
 
     return point;
 }
@@ -144,11 +144,11 @@ static PJ_COORD pipeline_forward_4d (PJ_COORD point, PJ *P) {
 static PJ_COORD pipeline_reverse_4d (PJ_COORD point, PJ *P) {
     int i, first_step, last_step;
 
-    first_step = P->opaque->steps;
+    first_step = static_cast<struct pj_opaque*>(P->opaque)->steps;
     last_step  =  0;
 
     for (i = first_step;  i != last_step;  i--)
-        point = proj_trans (P->opaque->pipeline[i], -1, point);
+        point = proj_trans (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i], PJ_INV, point);
 
     return point;
 }
@@ -161,8 +161,8 @@ static XYZ pipeline_forward_3d (LPZ lpz, PJ *P) {
     int i;
     point.lpz = lpz;
 
-    for (i = 1;  i <= P->opaque->steps;  i++)
-        point = pj_approx_3D_trans (P->opaque->pipeline[i], 1, point);
+    for (i = 1;  i <= static_cast<struct pj_opaque*>(P->opaque)->steps;  i++)
+        point = pj_approx_3D_trans (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i], PJ_FWD, point);
 
     return point.xyz;
 }
@@ -173,8 +173,8 @@ static LPZ pipeline_reverse_3d (XYZ xyz, PJ *P) {
     int i;
     point.xyz = xyz;
 
-    for (i = P->opaque->steps;  i > 0 ;  i--)
-        point = pj_approx_3D_trans (P->opaque->pipeline[i], -1, point);
+    for (i = static_cast<struct pj_opaque*>(P->opaque)->steps;  i > 0 ;  i--)
+        point = pj_approx_3D_trans (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i], PJ_INV, point);
 
     return point.lpz;
 }
@@ -187,8 +187,8 @@ static XY pipeline_forward (LP lp, PJ *P) {
     int i;
     point.lp = lp;
 
-    for (i = 1;  i <= P->opaque->steps;  i++)
-        point = pj_approx_2D_trans (P->opaque->pipeline[i], 1, point);
+    for (i = 1;  i <= static_cast<struct pj_opaque*>(P->opaque)->steps;  i++)
+        point = pj_approx_2D_trans (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i], PJ_FWD, point);
 
     return point.xy;
 }
@@ -198,8 +198,8 @@ static LP pipeline_reverse (XY xy, PJ *P) {
     PJ_COORD point = {{0,0,0,0}};
     int i;
     point.xy = xy;
-    for (i = P->opaque->steps;  i > 0 ;  i--)
-        point = pj_approx_2D_trans (P->opaque->pipeline[i], -1, point);
+    for (i = static_cast<struct pj_opaque*>(P->opaque)->steps;  i > 0 ;  i--)
+        point = pj_approx_2D_trans (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i], PJ_INV, point);
 
     return point.lp;
 }
@@ -207,7 +207,7 @@ static LP pipeline_reverse (XY xy, PJ *P) {
 
 
 
-static void *destructor (PJ *P, int errlev) {
+static PJ *destructor (PJ *P, int errlev) {
     int i;
     if (0==P)
         return 0;
@@ -216,13 +216,13 @@ static void *destructor (PJ *P, int errlev) {
         return pj_default_destructor (P, errlev);
 
     /* Deallocate each pipeine step, then pipeline array */
-    if (0!=P->opaque->pipeline)
-        for (i = 0;  i < P->opaque->steps; i++)
-            proj_destroy (P->opaque->pipeline[i+1]);
-    pj_dealloc (P->opaque->pipeline);
+    if (0!=static_cast<struct pj_opaque*>(P->opaque)->pipeline)
+        for (i = 0;  i < static_cast<struct pj_opaque*>(P->opaque)->steps; i++)
+            proj_destroy (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i+1]);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->pipeline);
 
-    pj_dealloc (P->opaque->argv);
-    pj_dealloc (P->opaque->current_argv);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->argv);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->current_argv);
 
     return pj_default_destructor(P, errlev);
 }
@@ -231,11 +231,11 @@ static void *destructor (PJ *P, int errlev) {
 static PJ *pj_create_pipeline (PJ *P, size_t steps) {
 
     /* Room for the pipeline: An array of PJ * with room for sentinels at both ends */
-    P->opaque->pipeline = pj_calloc (steps + 2, sizeof(PJ *));
-    if (0==P->opaque->pipeline)
+    static_cast<struct pj_opaque*>(P->opaque)->pipeline = static_cast<PJ**>(pj_calloc (steps + 2, sizeof(PJ *)));
+    if (0==static_cast<struct pj_opaque*>(P->opaque)->pipeline)
         return 0;
 
-    P->opaque->steps = (int)steps;
+    static_cast<struct pj_opaque*>(P->opaque)->steps = (int)steps;
 
     return P;
 }
@@ -260,7 +260,7 @@ static char *argv_sentinel = "step";
 static char **argv_params (paralist *params, size_t argc) {
     char **argv;
     size_t i = 0;
-    argv = pj_calloc (argc, sizeof (char *));
+    argv = static_cast<char**>(pj_calloc (argc, sizeof (char *)));
     if (0==argv)
         return 0;
     for (; params != 0; params = params->next)
@@ -350,16 +350,16 @@ PJ *OPERATION(pipeline,0) {
     P->skip_inv_finalize = 1;
 
 
-    P->opaque = pj_calloc (1, sizeof(struct pj_opaque));
+    P->opaque = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof(struct pj_opaque)));
     if (0==P->opaque)
         return destructor(P, ENOMEM);
 
     argc = (int)argc_params (P->params);
-    P->opaque->argv = argv = argv_params (P->params, argc);
+    static_cast<struct pj_opaque*>(P->opaque)->argv = argv = argv_params (P->params, argc);
     if (0==argv)
         return destructor (P, ENOMEM);
 
-    P->opaque->current_argv = current_argv = pj_calloc (argc, sizeof (char *));
+    static_cast<struct pj_opaque*>(P->opaque)->current_argv = current_argv = static_cast<char**>(pj_calloc (argc, sizeof (char *)));
     if (0==current_argv)
         return destructor (P, ENOMEM);
 
@@ -385,7 +385,7 @@ PJ *OPERATION(pipeline,0) {
         }
     }
     nsteps--; /* Last instance of +step is just a sentinel */
-    P->opaque->steps = nsteps;
+    static_cast<struct pj_opaque*>(P->opaque)->steps = nsteps;
 
     if (-1==i_pipeline)
         return destructor (P, PJD_ERR_MALFORMED_PIPELINE); /* ERROR: no pipeline def */
@@ -447,14 +447,14 @@ PJ *OPERATION(pipeline,0) {
                 next_step->inverted = next_step->inverted == 0 ? 1 : 0;
             }
 
-        P->opaque->pipeline[i+1] = next_step;
+        static_cast<struct pj_opaque*>(P->opaque)->pipeline[i+1] = next_step;
 
         proj_log_trace (P, "Pipeline at [%p]:    step at [%p] (%s) done", P, next_step, current_argv[0]);
     }
 
     /* Require a forward path through the pipeline */
     for (i = 1; i <= nsteps; i++) {
-        PJ *Q = P->opaque->pipeline[i];
+        PJ *Q = static_cast<struct pj_opaque*>(P->opaque)->pipeline[i];
         if ( ( Q->inverted && (Q->inv || Q->inv3d || Q->fwd4d) ) ||
              (!Q->inverted && (Q->fwd || Q->fwd3d || Q->fwd4d) ) ) {
             continue;
@@ -466,7 +466,7 @@ PJ *OPERATION(pipeline,0) {
 
     /* determine if an inverse operation is possible */
     for (i = 1; i <= nsteps; i++) {
-        PJ *Q = P->opaque->pipeline[i];
+        PJ *Q = static_cast<struct pj_opaque*>(P->opaque)->pipeline[i];
         if ( pj_has_inverse(Q) ) {
             continue;
         } else {
@@ -479,8 +479,8 @@ PJ *OPERATION(pipeline,0) {
 
     /* Check that output units from step i are compatible with expected units in step i+1 */
     for (i = 1; i < nsteps; i++) {
-        enum pj_io_units unit_returned = pj_right (P->opaque->pipeline[i]);
-        enum pj_io_units unit_expected = pj_left  (P->opaque->pipeline[i+1]);
+        enum pj_io_units unit_returned = pj_right (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i]);
+        enum pj_io_units unit_expected = pj_left  (static_cast<struct pj_opaque*>(P->opaque)->pipeline[i+1]);
 
         if ( unit_returned == PJ_IO_UNITS_WHATEVER || unit_expected == PJ_IO_UNITS_WHATEVER )
             continue;
@@ -493,9 +493,9 @@ PJ *OPERATION(pipeline,0) {
     proj_log_trace (P, "Pipeline: %d steps built. Determining i/o characteristics", nsteps);
 
     /* Determine forward input (= reverse output) data type */
-    P->left = pj_left (P->opaque->pipeline[1]);
+    P->left = pj_left (static_cast<struct pj_opaque*>(P->opaque)->pipeline[1]);
 
     /* Now, correspondingly determine forward output (= reverse input) data type */
-    P->right = pj_right (P->opaque->pipeline[nsteps]);
+    P->right = pj_right (static_cast<struct pj_opaque*>(P->opaque)->pipeline[nsteps]);
     return P;
 }
diff --git a/src/PJ_poly.c b/src/PJ_poly.cpp
index b5f78fdf..3bf7a8dd 100644
--- a/src/PJ_poly.c
+++ b/src/PJ_poly.cpp
@@ -23,7 +23,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  ms, sp, cp;
 
     if (fabs(lp.phi) <= TOL) {
@@ -42,7 +42,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  cot, E;
 
     if (fabs(lp.phi) <= TOL) {
@@ -60,7 +60,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     xy.y += Q->ml0;
     if (fabs(xy.y) <= TOL) {
@@ -131,22 +131,22 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 }
 
 
-static void *destructor(PJ *P, int errlev) {
+static PJ *destructor(PJ *P, int errlev) {
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    if (P->opaque->en)
-        pj_dealloc (P->opaque->en);
+    if (static_cast<struct pj_opaque*>(P->opaque)->en)
+        pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
 
     return pj_default_destructor(P, errlev);
 }
 
 
 PJ *PROJECTION(poly) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
 
diff --git a/src/PJ_putp2.c b/src/PJ_putp2.cpp
index d7a847c8..d7a847c8 100644
--- a/src/PJ_putp2.c
+++ b/src/PJ_putp2.cpp
diff --git a/src/PJ_putp3.c b/src/PJ_putp3.cpp
index 695ea877..6e85d35f 100644
--- a/src/PJ_putp3.c
+++ b/src/PJ_putp3.cpp
@@ -16,7 +16,7 @@ PROJ_HEAD(putp3p, "Putnins P3'") "\n\tPCyl, Sph";
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
 
-    xy.x = C * lp.lam * (1. - P->opaque->A * lp.phi * lp.phi);
+    xy.x = C * lp.lam * (1. - static_cast<struct pj_opaque*>(P->opaque)->A * lp.phi * lp.phi);
     xy.y = C * lp.phi;
 
     return xy;
@@ -27,14 +27,14 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
 
     lp.phi = xy.y / C;
-    lp.lam = xy.x / (C * (1. - P->opaque->A * lp.phi * lp.phi));
+    lp.lam = xy.x / (C * (1. - static_cast<struct pj_opaque*>(P->opaque)->A * lp.phi * lp.phi));
 
     return lp;
 }
 
 
 PJ *PROJECTION(putp3) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -49,7 +49,7 @@ PJ *PROJECTION(putp3) {
 }
 
 PJ *PROJECTION(putp3p) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_putp4p.c b/src/PJ_putp4p.cpp
index 6448dc19..77a18651 100644
--- a/src/PJ_putp4p.c
+++ b/src/PJ_putp4p.cpp
@@ -15,7 +15,7 @@ PROJ_HEAD(weren, "Werenskiold I") "\n\tPCyl, Sph";
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     lp.phi = aasin(P->ctx,0.883883476 * sin(lp.phi));
     xy.x = Q->C_x * lp.lam * cos(lp.phi);
@@ -28,7 +28,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     lp.phi = aasin(P->ctx,xy.y / Q->C_y);
     lp.lam = xy.x * cos(lp.phi) / Q->C_x;
@@ -41,7 +41,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(putp4p) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -58,7 +58,7 @@ PJ *PROJECTION(putp4p) {
 
 
 PJ *PROJECTION(weren) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_putp5.c b/src/PJ_putp5.cpp
index 96b0670d..d73e9368 100644
--- a/src/PJ_putp5.c
+++ b/src/PJ_putp5.cpp
@@ -18,7 +18,7 @@ PROJ_HEAD(putp5p, "Putnins P5'") "\n\tPCyl, Sph";
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     xy.x = C * lp.lam * (Q->A - Q->B * sqrt(1. + D * lp.phi * lp.phi));
     xy.y = C * lp.phi;
@@ -29,7 +29,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     lp.phi = xy.y / C;
     lp.lam = xy.x / (C * (Q->A - Q->B * sqrt(1. + D * lp.phi * lp.phi)));
@@ -40,7 +40,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(putp5) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -57,7 +57,7 @@ PJ *PROJECTION(putp5) {
 
 
 PJ *PROJECTION(putp5p) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_putp6.c b/src/PJ_putp6.cpp
index fa9290b4..fcd8146f 100644
--- a/src/PJ_putp6.c
+++ b/src/PJ_putp6.cpp
@@ -19,7 +19,7 @@ PROJ_HEAD(putp6p, "Putnins P6'") "\n\tPCyl, Sph";
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double p, r, V;
     int i;
 
@@ -43,7 +43,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double r;
 
     lp.phi = xy.y / Q->C_y;
@@ -56,7 +56,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 
 PJ *PROJECTION(putp6) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
@@ -76,7 +76,7 @@ PJ *PROJECTION(putp6) {
 
 
 PJ *PROJECTION(putp6p) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_qsc.c b/src/PJ_qsc.cpp
index 3b8b7fe2..767ed4a8 100644
--- a/src/PJ_qsc.c
+++ b/src/PJ_qsc.cpp
@@ -114,7 +114,7 @@ static double qsc_shift_lon_origin(double lon, double offset) {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double lat, lon;
     double theta, phi;
     double t, mu; /* nu; */
@@ -230,7 +230,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double mu, nu, cosmu, tannu;
     double tantheta, theta, cosphi, phi;
     double t;
@@ -370,7 +370,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 
 PJ *PROJECTION(qsc) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_robin.c b/src/PJ_robin.cpp
index 19bdc2dc..19bdc2dc 100644
--- a/src/PJ_robin.c
+++ b/src/PJ_robin.cpp
diff --git a/src/PJ_rpoly.c b/src/PJ_rpoly.cpp
index 03c2b161..24360965 100644
--- a/src/PJ_rpoly.c
+++ b/src/PJ_rpoly.cpp
@@ -19,7 +19,7 @@ PROJ_HEAD(rpoly, "Rectangular Polyconic")
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double fa;
 
     if (Q->mode)
@@ -40,7 +40,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 
 PJ *PROJECTION(rpoly) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_sch.c b/src/PJ_sch.cpp
index 64e5cdb8..4a0b1fb8 100644
--- a/src/PJ_sch.c
+++ b/src/PJ_sch.cpp
@@ -55,7 +55,7 @@ PROJ_HEAD(sch, "Spherical Cross-track Height") "\n\tMisc\n\tplat_0= plon_0= phdg
 
 static LPZ inverse3d(XYZ xyz, PJ *P) {
     LPZ lpz = {0.0, 0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double temp[3];
     double pxyz[3];
 
@@ -93,7 +93,7 @@ static LPZ inverse3d(XYZ xyz, PJ *P) {
 
 static XYZ forward3d(LPZ lpz, PJ *P) {
     XYZ xyz = {0.0, 0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double temp[3];
     double pxyz[3];
 
@@ -131,7 +131,7 @@ static XYZ forward3d(LPZ lpz, PJ *P) {
 
 
 static PJ *setup(PJ *P) { /* general initialization */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double reast, rnorth;
     double chdg, shdg;
     double clt, slt;
@@ -192,7 +192,7 @@ static PJ *setup(PJ *P) { /* general initialization */
 
 
 PJ *PROJECTION(sch) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_sconics.c b/src/PJ_sconics.cpp
index ce044c24..4efec86f 100644
--- a/src/PJ_sconics.c
+++ b/src/PJ_sconics.cpp
@@ -51,8 +51,8 @@ static int phi12(PJ *P, double *del) {
         p1 = pj_param(P->ctx, P->params, "rlat_1").f;
         p2 = pj_param(P->ctx, P->params, "rlat_2").f;
         *del = 0.5 * (p2 - p1);
-        P->opaque->sig = 0.5 * (p2 + p1);
-        err = (fabs(*del) < EPS || fabs(P->opaque->sig) < EPS) ? PJD_ERR_ABS_LAT1_EQ_ABS_LAT2 : 0;
+        static_cast<struct pj_opaque*>(P->opaque)->sig = 0.5 * (p2 + p1);
+        err = (fabs(*del) < EPS || fabs(static_cast<struct pj_opaque*>(P->opaque)->sig) < EPS) ? PJD_ERR_ABS_LAT1_EQ_ABS_LAT2 : 0;
     }
     return err;
 }
@@ -60,7 +60,7 @@ static int phi12(PJ *P, double *del) {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double rho;
 
     switch (Q->type) {
@@ -83,7 +83,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {  /* Spheroidal, (and ellipsoidal?) inverse */
     LP lp = {0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double rho;
 
     rho = hypot (xy.x,  xy.y = Q->rho_0 - xy.y);
@@ -112,7 +112,7 @@ static LP s_inverse (XY xy, PJ *P) {  /* Spheroidal, (and ellipsoidal?) inverse
 static PJ *setup(PJ *P, enum Type type) {
     double del, cs;
     int err;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_somerc.c b/src/PJ_somerc.cpp
index c6c3ff21..6a98f76f 100644
--- a/src/PJ_somerc.c
+++ b/src/PJ_somerc.cpp
@@ -19,7 +19,7 @@ struct pj_opaque {
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0, 0.0};
     double phip, lamp, phipp, lampp, sp, cp;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     sp = P->e * sin (lp.phi);
     phip = 2.* atan ( exp ( Q->c * (
@@ -37,7 +37,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double phip, lamp, phipp, lampp, cp, esp, con, delp;
     int i;
 
@@ -69,7 +69,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 PJ *PROJECTION(somerc) {
     double cp, phip0, sp;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_stere.c b/src/PJ_stere.cpp
index 82fd5c07..94e7f91d 100644
--- a/src/PJ_stere.c
+++ b/src/PJ_stere.cpp
@@ -23,8 +23,8 @@ struct pj_opaque {
     enum Mode mode;
 };
 
-#define sinph0  P->opaque->sinX1
-#define cosph0  P->opaque->cosX1
+#define sinph0  static_cast<struct pj_opaque*>(P->opaque)->sinX1
+#define cosph0  static_cast<struct pj_opaque*>(P->opaque)->cosX1
 #define EPS10   1.e-10
 #define TOL 1.e-8
 #define NITER   8
@@ -39,7 +39,7 @@ static double ssfn_ (double phit, double sinphi, double eccen) {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double coslam, sinlam, sinX = 0.0, cosX = 0.0, X, A = 0.0, sinphi;
 
     coslam = cos (lp.lam);
@@ -87,7 +87,7 @@ xmul:
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  sinphi, cosphi, coslam, sinlam;
 
     sinphi = sin(lp.phi);
@@ -129,7 +129,7 @@ oblcon:
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cosphi, sinphi, tp=0.0, phi_l=0.0, rho, halfe=0.0, halfpi=0.0;
     int i;
 
@@ -179,7 +179,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double  c, rh, sinc, cosc;
 
     sinc = sin (c = 2. * atan ((rh = hypot (xy.x, xy.y)) / Q->akm1));
@@ -220,7 +220,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 static PJ *setup(PJ *P) {                   /* general initialization */
     double t;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     if (fabs ((t = fabs (P->phi0)) - M_HALFPI) < EPS10)
         Q->mode = P->phi0 < 0. ? S_POLE : N_POLE;
@@ -281,7 +281,7 @@ static PJ *setup(PJ *P) {                   /* general initialization */
 
 
 PJ *PROJECTION(stere) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -294,7 +294,7 @@ PJ *PROJECTION(stere) {
 
 
 PJ *PROJECTION(ups) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_sterea.c b/src/PJ_sterea.cpp
index eb4c9f2c..4c2fe2a3 100644
--- a/src/PJ_sterea.c
+++ b/src/PJ_sterea.cpp
@@ -43,7 +43,7 @@ PROJ_HEAD(sterea, "Oblique Stereographic Alternative") "\n\tAzimuthal, Sph&Ell";
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cosc, sinc, cosl, k;
 
     lp = pj_gauss(P->ctx, lp, Q->en);
@@ -59,7 +59,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double rho, c, sinc, cosc;
 
     xy.x /= P->k0;
@@ -78,21 +78,21 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 }
 
 
-static void *destructor (PJ *P, int errlev) {
+static PJ *destructor (PJ *P, int errlev) {
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor (P, errlev);
 }
 
 
 PJ *PROJECTION(sterea) {
     double R;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
 
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
diff --git a/src/PJ_sts.c b/src/PJ_sts.cpp
index 66094178..4aece68e 100644
--- a/src/PJ_sts.c
+++ b/src/PJ_sts.cpp
@@ -19,7 +19,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 	double c;
 
 	xy.x = Q->C_x * lp.lam * cos(lp.phi);
@@ -39,7 +39,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 	double c;
 
 	xy.y /= Q->C_y;
@@ -58,17 +58,17 @@ static PJ *setup(PJ *P, double p, double q, int mode) {
 	P->es  = 0.;
 	P->inv = s_inverse;
 	P->fwd = s_forward;
-	P->opaque->C_x = q / p;
-	P->opaque->C_y = p;
-	P->opaque->C_p = 1/ q;
-	P->opaque->tan_mode = mode;
+	static_cast<struct pj_opaque*>(P->opaque)->C_x = q / p;
+	static_cast<struct pj_opaque*>(P->opaque)->C_y = p;
+	static_cast<struct pj_opaque*>(P->opaque)->C_p = 1/ q;
+	static_cast<struct pj_opaque*>(P->opaque)->tan_mode = mode;
 	return P;
 }
 
 
 
 PJ *PROJECTION(fouc) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
@@ -78,7 +78,7 @@ PJ *PROJECTION(fouc) {
 
 
 PJ *PROJECTION(kav5) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
@@ -89,7 +89,7 @@ PJ *PROJECTION(kav5) {
 
 
 PJ *PROJECTION(qua_aut) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
@@ -99,7 +99,7 @@ PJ *PROJECTION(qua_aut) {
 
 
 PJ *PROJECTION(mbt_s) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_tcc.c b/src/PJ_tcc.cpp
index 60ded63e..60ded63e 100644
--- a/src/PJ_tcc.c
+++ b/src/PJ_tcc.cpp
diff --git a/src/PJ_tcea.c b/src/PJ_tcea.cpp
index d30f3df0..d30f3df0 100644
--- a/src/PJ_tcea.c
+++ b/src/PJ_tcea.cpp
diff --git a/src/PJ_times.c b/src/PJ_times.cpp
index e8b4499f..e8b4499f 100644
--- a/src/PJ_times.c
+++ b/src/PJ_times.cpp
diff --git a/src/PJ_tmerc.c b/src/PJ_tmerc.cpp
index 069cdc2c..55f878c9 100644
--- a/src/PJ_tmerc.c
+++ b/src/PJ_tmerc.cpp
@@ -28,7 +28,7 @@ struct pj_opaque {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double al, als, n, cosphi, sinphi, t;
 
     /*
@@ -93,7 +93,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
         return xy;
     }
 
-    xy.x = P->opaque->ml0 * log ((1. + b) / (1. - b));
+    xy.x = static_cast<struct pj_opaque*>(P->opaque)->ml0 * log ((1. + b) / (1. - b));
     xy.y = cosphi * cos (lp.lam) / sqrt (1. - b * b);
 
     b = fabs ( xy.y );
@@ -108,14 +108,14 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
     if (lp.phi < 0.)
         xy.y = -xy.y;
-    xy.y = P->opaque->esp * (xy.y - P->phi0);
+    xy.y = static_cast<struct pj_opaque*>(P->opaque)->esp * (xy.y - P->phi0);
     return xy;
 }
 
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double n, con, cosphi, d, ds, sinphi, t;
 
     lp.phi = pj_inv_mlfn(P->ctx, Q->ml0 + xy.y / P->k0, P->es, Q->en);
@@ -151,9 +151,9 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0, 0.0};
     double h, g;
 
-    h = exp(xy.x / P->opaque->esp);
+    h = exp(xy.x / static_cast<struct pj_opaque*>(P->opaque)->esp);
     g = .5 * (h - 1. / h);
-    h = cos (P->phi0 + xy.y / P->opaque->esp);
+    h = cos (P->phi0 + xy.y / static_cast<struct pj_opaque*>(P->opaque)->esp);
     lp.phi = asin(sqrt((1. - h * h) / (1. + g * g)));
 
     /* Make sure that phi is on the correct hemisphere when false northing is used */
@@ -164,20 +164,20 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 }
 
 
-static void *destructor(PJ *P, int errlev) {                       /* Destructor */
+static PJ *destructor(PJ *P, int errlev) {                       /* Destructor */
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor(P, errlev);
 
-    pj_dealloc (P->opaque->en);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
     return pj_default_destructor(P, errlev);
 }
 
 
 static PJ *setup(PJ *P) {                   /* general initialization */
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     if (P->es != 0.0) {
         if (!(Q->en = pj_enfn(P->es)))
             return pj_default_destructor(P, ENOMEM);
@@ -197,7 +197,7 @@ static PJ *setup(PJ *P) {                   /* general initialization */
 
 
 PJ *PROJECTION(tmerc) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
 
diff --git a/src/PJ_tobmerc.c b/src/PJ_tobmerc.cpp
index 9c939f0b..9c939f0b 100644
--- a/src/PJ_tobmerc.c
+++ b/src/PJ_tobmerc.cpp
diff --git a/src/PJ_tpeqd.c b/src/PJ_tpeqd.cpp
index 87877ec1..5691cd7b 100644
--- a/src/PJ_tpeqd.c
+++ b/src/PJ_tpeqd.cpp
@@ -16,7 +16,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double t, z1, z2, dl1, dl2, sp, cp;
 
     sp = sin(lp.phi);
@@ -37,7 +37,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double cz1, cz2, s, d, cp, sp;
 
     cz1 = cos (hypot(xy.y, xy.x + Q->hz0));
@@ -59,7 +59,7 @@ static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
 
 PJ *PROJECTION(tpeqd) {
     double lam_1, lam_2, phi_1, phi_2, A12, pp;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_unitconvert.c b/src/PJ_unitconvert.cpp
index 402941a4..7476620e 100644
--- a/src/PJ_unitconvert.c
+++ b/src/PJ_unitconvert.cpp
@@ -431,7 +431,7 @@ static double get_unit_conversion_factor(const char* name,
 /***********************************************************************/
 PJ *CONVERSION(unitconvert,0) {
 /***********************************************************************/
-    struct pj_opaque_unitconvert *Q = pj_calloc (1, sizeof (struct pj_opaque_unitconvert));
+    struct pj_opaque_unitconvert *Q = static_cast<struct pj_opaque_unitconvert*>(pj_calloc (1, sizeof (struct pj_opaque_unitconvert)));
     char *s, *name;
     int i;
     double f;
diff --git a/src/PJ_urm5.c b/src/PJ_urm5.cpp
index 293de8cf..6a208647 100644
--- a/src/PJ_urm5.c
+++ b/src/PJ_urm5.cpp
@@ -15,7 +15,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0, 0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double t;
 
     t = lp.phi = aasin (P->ctx, Q->n * sin (lp.phi));
@@ -28,7 +28,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 PJ *PROJECTION(urm5) {
     double alpha, t;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_urmfps.c b/src/PJ_urmfps.cpp
index 467fc9bc..1d147b9c 100644
--- a/src/PJ_urmfps.c
+++ b/src/PJ_urmfps.cpp
@@ -19,24 +19,24 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0, 0.0};
-    lp.phi = aasin (P->ctx,P->opaque->n * sin (lp.phi));
+    lp.phi = aasin (P->ctx,static_cast<struct pj_opaque*>(P->opaque)->n * sin (lp.phi));
     xy.x = C_x * lp.lam * cos (lp.phi);
-    xy.y = P->opaque->C_y * lp.phi;
+    xy.y = static_cast<struct pj_opaque*>(P->opaque)->C_y * lp.phi;
     return xy;
 }
 
 
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0, 0.0};
-    xy.y /= P->opaque->C_y;
-    lp.phi = aasin(P->ctx, sin (xy.y) / P->opaque->n);
+    xy.y /= static_cast<struct pj_opaque*>(P->opaque)->C_y;
+    lp.phi = aasin(P->ctx, sin (xy.y) / static_cast<struct pj_opaque*>(P->opaque)->n);
     lp.lam = xy.x / (C_x * cos (xy.y));
     return lp;
 }
 
 
 static PJ *setup(PJ *P) {
-    P->opaque->C_y = Cy / P->opaque->n;
+    static_cast<struct pj_opaque*>(P->opaque)->C_y = Cy / static_cast<struct pj_opaque*>(P->opaque)->n;
     P->es = 0.;
     P->inv = s_inverse;
     P->fwd = s_forward;
@@ -45,15 +45,15 @@ static PJ *setup(PJ *P) {
 
 
 PJ *PROJECTION(urmfps) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
 
     P->opaque = Q;
 
     if (pj_param(P->ctx, P->params, "tn").i) {
-        P->opaque->n = pj_param(P->ctx, P->params, "dn").f;
-        if (P->opaque->n <= 0. || P->opaque->n > 1.)
+        static_cast<struct pj_opaque*>(P->opaque)->n = pj_param(P->ctx, P->params, "dn").f;
+        if (static_cast<struct pj_opaque*>(P->opaque)->n <= 0. || static_cast<struct pj_opaque*>(P->opaque)->n > 1.)
             return pj_default_destructor(P, PJD_ERR_N_OUT_OF_RANGE);
     } else {
         return pj_default_destructor(P, PJD_ERR_N_OUT_OF_RANGE);
@@ -64,11 +64,11 @@ PJ *PROJECTION(urmfps) {
 
 
 PJ *PROJECTION(wag1) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
 
-    P->opaque->n = 0.8660254037844386467637231707;
+    static_cast<struct pj_opaque*>(P->opaque)->n = 0.8660254037844386467637231707;
     return setup(P);
 }
diff --git a/src/PJ_vandg.c b/src/PJ_vandg.cpp
index d148e210..d148e210 100644
--- a/src/PJ_vandg.c
+++ b/src/PJ_vandg.cpp
diff --git a/src/PJ_vandg2.c b/src/PJ_vandg2.cpp
index 447cb782..588366cf 100644
--- a/src/PJ_vandg2.c
+++ b/src/PJ_vandg2.cpp
@@ -17,7 +17,7 @@ PROJ_HEAD(vandg3, "van der Grinten III") "\n\tMisc Sph, no inv";
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double x1, at, bt, ct;
 
     bt = fabs(M_TWO_D_PI * lp.phi);
@@ -49,7 +49,7 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 
 
 PJ *PROJECTION(vandg2) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -61,7 +61,7 @@ PJ *PROJECTION(vandg2) {
 }
 
 PJ *PROJECTION(vandg3) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/PJ_vandg4.c b/src/PJ_vandg4.cpp
index d9a53c87..d9a53c87 100644
--- a/src/PJ_vandg4.c
+++ b/src/PJ_vandg4.cpp
diff --git a/src/PJ_vgridshift.c b/src/PJ_vgridshift.cpp
index ac5d26ef..8aad3777 100644
--- a/src/PJ_vgridshift.c
+++ b/src/PJ_vgridshift.cpp
@@ -83,7 +83,7 @@ static PJ_COORD reverse_4d(PJ_COORD obs, PJ *P) {
 
 
 PJ *TRANSFORMATION(vgridshift,0) {
-    struct pj_opaque_vgridshift *Q = pj_calloc (1, sizeof (struct pj_opaque_vgridshift));
+    struct pj_opaque_vgridshift *Q = static_cast<struct pj_opaque_vgridshift*>(pj_calloc (1, sizeof (struct pj_opaque_vgridshift)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = (void *) Q;
diff --git a/src/PJ_wag2.c b/src/PJ_wag2.cpp
index 1bee737a..1bee737a 100644
--- a/src/PJ_wag2.c
+++ b/src/PJ_wag2.cpp
diff --git a/src/PJ_wag3.c b/src/PJ_wag3.cpp
index ccd19d4d..0eeb73df 100644
--- a/src/PJ_wag3.c
+++ b/src/PJ_wag3.cpp
@@ -16,7 +16,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-	xy.x = P->opaque->C_x * lp.lam * cos(TWOTHIRD * lp.phi);
+	xy.x = static_cast<struct pj_opaque*>(P->opaque)->C_x * lp.lam * cos(TWOTHIRD * lp.phi);
 	xy.y = lp.phi;
 	return xy;
 }
@@ -25,21 +25,21 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
 	lp.phi = xy.y;
-	lp.lam = xy.x / (P->opaque->C_x * cos(TWOTHIRD * lp.phi));
+	lp.lam = xy.x / (static_cast<struct pj_opaque*>(P->opaque)->C_x * cos(TWOTHIRD * lp.phi));
 	return lp;
 }
 
 
 PJ *PROJECTION(wag3) {
 	double ts;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
 
     P->opaque = Q;
 
 	ts = pj_param (P->ctx, P->params, "rlat_ts").f;
-	P->opaque->C_x = cos (ts) / cos (2.*ts/3.);
+	static_cast<struct pj_opaque*>(P->opaque)->C_x = cos (ts) / cos (2.*ts/3.);
 	P->es = 0.;
     P->inv = s_inverse;
     P->fwd = s_forward;
diff --git a/src/PJ_wag7.c b/src/PJ_wag7.cpp
index 2009e672..2009e672 100644
--- a/src/PJ_wag7.c
+++ b/src/PJ_wag7.cpp
diff --git a/src/PJ_wink1.c b/src/PJ_wink1.cpp
index 865cc6ac..6640f995 100644
--- a/src/PJ_wink1.c
+++ b/src/PJ_wink1.cpp
@@ -15,7 +15,7 @@ struct pj_opaque {
 
 static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
     XY xy = {0.0,0.0};
-	xy.x = .5 * lp.lam * (P->opaque->cosphi1 + cos(lp.phi));
+	xy.x = .5 * lp.lam * (static_cast<struct pj_opaque*>(P->opaque)->cosphi1 + cos(lp.phi));
 	xy.y = lp.phi;
 	return (xy);
 }
@@ -24,18 +24,18 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 static LP s_inverse (XY xy, PJ *P) {           /* Spheroidal, inverse */
     LP lp = {0.0,0.0};
 	lp.phi = xy.y;
-	lp.lam = 2. * xy.x / (P->opaque->cosphi1 + cos(lp.phi));
+	lp.lam = 2. * xy.x / (static_cast<struct pj_opaque*>(P->opaque)->cosphi1 + cos(lp.phi));
 	return (lp);
 }
 
 
 PJ *PROJECTION(wink1) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
 
-	P->opaque->cosphi1 = cos (pj_param(P->ctx, P->params, "rlat_ts").f);
+	static_cast<struct pj_opaque*>(P->opaque)->cosphi1 = cos (pj_param(P->ctx, P->params, "rlat_ts").f);
 	P->es = 0.;
     P->inv = s_inverse;
     P->fwd = s_forward;
diff --git a/src/PJ_wink2.c b/src/PJ_wink2.cpp
index f8e9af09..9da65eaa 100644
--- a/src/PJ_wink2.c
+++ b/src/PJ_wink2.cpp
@@ -31,19 +31,19 @@ static XY s_forward (LP lp, PJ *P) {           /* Spheroidal, forward */
 		lp.phi = (lp.phi < 0.) ? -M_HALFPI : M_HALFPI;
 	else
 		lp.phi *= 0.5;
-	xy.x = 0.5 * lp.lam * (cos (lp.phi) + P->opaque->cosphi1);
+	xy.x = 0.5 * lp.lam * (cos (lp.phi) + static_cast<struct pj_opaque*>(P->opaque)->cosphi1);
 	xy.y = M_FORTPI * (sin (lp.phi) + xy.y);
 	return xy;
 }
 
 
 PJ *PROJECTION(wink2) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
 
-	P->opaque->cosphi1 = cos(pj_param(P->ctx, P->params, "rlat_1").f);
+	static_cast<struct pj_opaque*>(P->opaque)->cosphi1 = cos(pj_param(P->ctx, P->params, "rlat_1").f);
 	P->es  = 0.;
     P->inv = 0;
     P->fwd = s_forward;
diff --git a/src/aasincos.c b/src/aasincos.cpp
index 4f9ea25f..4f9ea25f 100644
--- a/src/aasincos.c
+++ b/src/aasincos.cpp
diff --git a/src/adjlon.c b/src/adjlon.cpp
index 784a90aa..784a90aa 100644
--- a/src/adjlon.c
+++ b/src/adjlon.cpp
diff --git a/src/bch2bps.c b/src/bch2bps.cpp
index 3ee56993..3ee56993 100644
--- a/src/bch2bps.c
+++ b/src/bch2bps.cpp
diff --git a/src/bchgen.c b/src/bchgen.cpp
index c129f0c1..c129f0c1 100644
--- a/src/bchgen.c
+++ b/src/bchgen.cpp
diff --git a/src/bin_cct.cmake b/src/bin_cct.cmake
index 37752217..11643bca 100644
--- a/src/bin_cct.cmake
+++ b/src/bin_cct.cmake
@@ -1,4 +1,4 @@
-set(CCT_SRC cct.c proj_strtod.c proj_strtod.h)
+set(CCT_SRC cct.cpp proj_strtod.cpp proj_strtod.h)
 set(CCT_INCLUDE optargpm.h)
 
 source_group("Source Files\\Bin" FILES ${CCT_SRC})
diff --git a/src/bin_cs2cs.cmake b/src/bin_cs2cs.cmake
index 9c013dcc..70d3b04d 100644
--- a/src/bin_cs2cs.cmake
+++ b/src/bin_cs2cs.cmake
@@ -1,6 +1,6 @@
 set(CS2CS_SRC cs2cs.cpp
-              gen_cheb.c 
-              p_series.c)
+              gen_cheb.cpp 
+              p_series.cpp)
 
 source_group("Source Files\\Bin" FILES ${CS2CS_SRC})
 
diff --git a/src/bin_geod.cmake b/src/bin_geod.cmake
index 1f9ee788..fe0e5c08 100644
--- a/src/bin_geod.cmake
+++ b/src/bin_geod.cmake
@@ -1,5 +1,5 @@
-set(GEOD_SRC geod.c
-             geod_set.c geod_interface.c )
+set(GEOD_SRC geod.cpp
+             geod_set.cpp geod_interface.cpp )
 set(GEOD_INCLUDE geod_interface.h)
 
 source_group("Source Files\\Bin" FILES ${GEOD_SRC} ${GEOD_INCLUDE})
diff --git a/src/bin_geodtest.cmake b/src/bin_geodtest.cmake
index 743c630e..bfd6cf99 100644
--- a/src/bin_geodtest.cmake
+++ b/src/bin_geodtest.cmake
@@ -1,4 +1,4 @@
-set(GEODTEST_SRC geodtest.c )
+set(GEODTEST_SRC geodtest.cpp )
 set(GEODTEST_INCLUDE)
 
 source_group("Source Files\\Bin" FILES ${GEODTEST_SRC} ${GEODTEST_INCLUDE})
diff --git a/src/bin_gie.cmake b/src/bin_gie.cmake
index 596592fa..f59319fc 100644
--- a/src/bin_gie.cmake
+++ b/src/bin_gie.cmake
@@ -1,4 +1,4 @@
-set(GIE_SRC gie.c proj_strtod.c proj_strtod.h)
+set(GIE_SRC gie.cpp proj_strtod.cpp proj_strtod.h)
 set(GIE_INCLUDE optargpm.h)
 
 source_group("Source Files\\Bin" FILES ${GIE_SRC})
diff --git a/src/bin_nad2bin.cmake b/src/bin_nad2bin.cmake
index 0d0fd473..3e1fa422 100644
--- a/src/bin_nad2bin.cmake
+++ b/src/bin_nad2bin.cmake
@@ -3,7 +3,7 @@ if(WIN32 AND BUILD_LIBPROJ_SHARED)
 endif(WIN32 AND BUILD_LIBPROJ_SHARED)
 
 
-set(NAD2BIN_SRC nad2bin.c)
+set(NAD2BIN_SRC nad2bin.cpp)
 source_group("Source Files\\Bin" FILES ${NAD2BIN_SRC})
 
 #Executable
diff --git a/src/bin_proj.cmake b/src/bin_proj.cmake
index fb7c885d..5911aa50 100644
--- a/src/bin_proj.cmake
+++ b/src/bin_proj.cmake
@@ -1,6 +1,6 @@
-set(PROJ_SRC proj.c 
-             gen_cheb.c 
-             p_series.c)
+set(PROJ_SRC proj.cpp 
+             gen_cheb.cpp 
+             p_series.cpp)
 
 source_group("Source Files\\Bin" FILES ${PROJ_SRC})
 
diff --git a/src/biveval.c b/src/biveval.cpp
index 05e83e21..05e83e21 100644
--- a/src/biveval.c
+++ b/src/biveval.cpp
diff --git a/src/cct.c b/src/cct.cpp
index 54734b98..0493e721 100644
--- a/src/cct.c
+++ b/src/cct.cpp
@@ -211,7 +211,7 @@ int main(int argc, char **argv) {
     char *comment;
     char *comment_delimiter;
     char *buf;
-    int i, nfields = 4, direction = 1, skip_lines = 0, verbose;
+    int i, nfields = 4, skip_lines = 0, verbose;
     double fixed_z = HUGE_VAL, fixed_time = HUGE_VAL;
     int decimals_angles = 10;
     int decimals_distances = 4;
@@ -237,10 +237,10 @@ int main(int argc, char **argv) {
         return 0;
     }
 
-    direction = opt_given (o, "I")? -1: 1;
+    PJ_DIRECTION direction = opt_given (o, "I")? PJ_INV: PJ_FWD;
 
     verbose   = MIN(opt_given (o, "v"), 3); /* log level can't be larger than 3 */
-    proj_log_level (PJ_DEFAULT_CTX, verbose);
+    proj_log_level (PJ_DEFAULT_CTX, static_cast<PJ_LOG_LEVEL>(verbose));
     proj_log_func  (PJ_DEFAULT_CTX, (void *) fout, logger);
 
     if (opt_given (o, "version")) {
@@ -309,7 +309,7 @@ int main(int argc, char **argv) {
     info = proj_pj_info (P);
     print (PJ_LOG_TRACE, "Final: %s argc=%d pargc=%d\n", info.definition, argc, o->pargc);
 
-    if (direction==-1) {
+    if (direction== PJ_INV) {
         /* fail if an inverse operation is not available */
         if (!info.has_inverse) {
             print (PJ_LOG_ERROR, "Inverse operation not available\n");
@@ -320,10 +320,10 @@ int main(int argc, char **argv) {
         /* We have no API call for inverting an operation, so we brute force it. */
         P->inverted = !(P->inverted);
     }
-    direction = 1;
+    direction = PJ_FWD;
 
     /* Allocate input buffer */
-    buf = calloc (1, 10000);
+    buf = static_cast<char*>(calloc (1, 10000));
     if (0==buf) {
         print (PJ_LOG_ERROR, "%s: Out of memory\n", o->progname);
         pj_free (P);
diff --git a/src/dmstor.c b/src/dmstor.cpp
index ab8e33f4..967a9f18 100644
--- a/src/dmstor.c
+++ b/src/dmstor.cpp
@@ -27,7 +27,8 @@ dmstor(const char *is, char **rs) {
 	double
 dmstor_ctx(projCtx ctx, const char *is, char **rs) {
 	int sign, n, nl;
-	char *p, *s, work[MAX_WORK];
+	char *s, work[MAX_WORK];
+        const char* p;
 	double v, tv;
 
 	if (rs)
diff --git a/src/emess.c b/src/emess.cpp
index eb2ac9d6..eb2ac9d6 100644
--- a/src/emess.c
+++ b/src/emess.cpp
diff --git a/src/gen_cheb.c b/src/gen_cheb.cpp
index ab16b409..ab16b409 100644
--- a/src/gen_cheb.c
+++ b/src/gen_cheb.cpp
diff --git a/src/geocent.c b/src/geocent.cpp
index c023bdd3..c023bdd3 100644
--- a/src/geocent.c
+++ b/src/geocent.cpp
diff --git a/src/geod.c b/src/geod.cpp
index bb52818e..bb52818e 100644
--- a/src/geod.c
+++ b/src/geod.cpp
diff --git a/src/geod_interface.c b/src/geod_interface.cpp
index a30377ac..a30377ac 100644
--- a/src/geod_interface.c
+++ b/src/geod_interface.cpp
diff --git a/src/geod_set.c b/src/geod_set.cpp
index b5bd0667..b5bd0667 100644
--- a/src/geod_set.c
+++ b/src/geod_set.cpp
diff --git a/src/geodesic.c b/src/geodesic.cpp
index 220dcd7f..220dcd7f 100644
--- a/src/geodesic.c
+++ b/src/geodesic.cpp
diff --git a/src/geodtest.c b/src/geodtest.cpp
index 0ee86d5c..0ee86d5c 100644
--- a/src/geodtest.c
+++ b/src/geodtest.cpp
diff --git a/src/gie.c b/src/gie.cpp
index 4bb79f1f..74d78db5 100644
--- a/src/gie.c
+++ b/src/gie.cpp
@@ -1195,20 +1195,20 @@ static ffio *ffio_create (const char **tags, size_t n_tags, size_t max_record_si
 /****************************************************************************************
 Constructor for the ffio object.
 ****************************************************************************************/
-    ffio *G = calloc (1, sizeof (ffio));
+    ffio *G = static_cast<ffio*>(calloc (1, sizeof (ffio)));
     if (0==G)
         return 0;
 
     if (0==max_record_size)
         max_record_size = 1000;
 
-    G->args = calloc (1, 5*max_record_size);
+    G->args = static_cast<char*>(calloc (1, 5*max_record_size));
     if (0==G->args) {
         free (G);
         return 0;
     }
 
-    G->next_args = calloc (1, max_record_size);
+    G->next_args = static_cast<char*>(calloc (1, max_record_size));
     if (0==G->args) {
         free (G->args);
         free (G);
@@ -1412,7 +1412,7 @@ static int append_args (ffio *G) {
 
     /* +2: 1 for the space separator and 1 for the NUL termination. */
     if (G->args_size < args_len + next_len - skip_chars + 2) {
-        void *p = realloc (G->args, 2 * G->args_size);
+        char *p = static_cast<char*>(realloc (G->args, 2 * G->args_size));
         if (0==p)
             return 0;
         G->args = p;
diff --git a/src/jniproj.c b/src/jniproj.cpp
index 67aa2478..67aa2478 100644
--- a/src/jniproj.c
+++ b/src/jniproj.cpp
diff --git a/src/lib_proj.cmake b/src/lib_proj.cmake
index 4f29f4d5..7be6302b 100644
--- a/src/lib_proj.cmake
+++ b/src/lib_proj.cmake
@@ -55,195 +55,195 @@ endif()
 ###  library source list and include_list  ###
 ##############################################
 SET(SRC_LIBPROJ_PJ
-        nad_init.c
-        PJ_aea.c
-        PJ_aeqd.c
-        PJ_affine.c
-        PJ_airy.c
-        PJ_aitoff.c
-        PJ_august.c
-        PJ_axisswap.c
-        PJ_bacon.c
-        PJ_bertin1953.c
-        PJ_bipc.c
-        PJ_boggs.c
-        PJ_bonne.c
-        PJ_calcofi.c
-        PJ_cart.c
-        PJ_cass.c
-        PJ_cc.c
-        PJ_ccon.c
-        PJ_cea.c
-        PJ_chamb.c
-        PJ_collg.c
-        PJ_comill.c
-        PJ_crast.c
-        PJ_deformation.c
-        PJ_denoy.c
-        PJ_eck1.c
-        PJ_eck2.c
-        PJ_eck3.c
-        PJ_eck4.c
-        PJ_eck5.c
-        PJ_eqc.c
-        PJ_eqdc.c
-        PJ_eqearth.c
-        PJ_fahey.c
-        PJ_fouc_s.c
-        PJ_gall.c
-        PJ_geoc.c
-        PJ_geos.c
-        PJ_gins8.c
-        PJ_gnom.c
-        PJ_gn_sinu.c
-        PJ_goode.c
-        PJ_gstmerc.c
-        PJ_hammer.c
-        PJ_hatano.c
-        PJ_helmert.c
-        PJ_hgridshift.c
-        PJ_horner.c
-        PJ_igh.c
-        PJ_isea.c
-        PJ_imw_p.c
-        PJ_krovak.c
-        PJ_labrd.c
-        PJ_laea.c
-        PJ_lagrng.c
-        PJ_larr.c
-        PJ_lask.c
-        PJ_latlong.c
-        PJ_lcca.c
-        PJ_lcc.c
-        PJ_loxim.c
-        PJ_lsat.c
-        PJ_misrsom.c
-        PJ_mbt_fps.c
-        PJ_mbtfpp.c
-        PJ_mbtfpq.c
-        PJ_merc.c
-        PJ_mill.c
-        PJ_mod_ster.c
-        PJ_moll.c
-        PJ_molodensky.c
-        PJ_natearth.c
-        PJ_natearth2.c
-        PJ_nell.c
-        PJ_nell_h.c
-        PJ_nocol.c
-        PJ_nsper.c
-        PJ_nzmg.c
-        PJ_ob_tran.c
-        PJ_ocea.c
-        PJ_oea.c
-        PJ_omerc.c
-        PJ_ortho.c
-        PJ_patterson.c
-        PJ_pipeline.c
-        PJ_poly.c
-        PJ_putp2.c
-        PJ_putp3.c
-        PJ_putp4p.c
-        PJ_putp5.c
-        PJ_putp6.c
-        PJ_qsc.c
-        PJ_robin.c
-        PJ_rpoly.c
-        PJ_sch.c
-        PJ_sconics.c
-        PJ_somerc.c
-        PJ_sterea.c
-        PJ_stere.c
-        PJ_sts.c
-        PJ_tcc.c
-        PJ_tcea.c
-        PJ_times.c
-        PJ_tmerc.c
-        PJ_tobmerc.c
-        PJ_tpeqd.c
-        PJ_unitconvert.c
-        PJ_urm5.c
-        PJ_urmfps.c
-        PJ_vandg.c
-        PJ_vandg2.c
-        PJ_vandg4.c
-        PJ_vgridshift.c
-        PJ_wag2.c
-        PJ_wag3.c
-        PJ_wag7.c
-        PJ_wink1.c
-        PJ_wink2.c
-        proj_etmerc.c
+        nad_init.cpp
+        PJ_aea.cpp
+        PJ_aeqd.cpp
+        PJ_affine.cpp
+        PJ_airy.cpp
+        PJ_aitoff.cpp
+        PJ_august.cpp
+        PJ_axisswap.cpp
+        PJ_bacon.cpp
+        PJ_bertin1953.cpp
+        PJ_bipc.cpp
+        PJ_boggs.cpp
+        PJ_bonne.cpp
+        PJ_calcofi.cpp
+        PJ_cart.cpp
+        PJ_cass.cpp
+        PJ_cc.cpp
+        PJ_ccon.cpp
+        PJ_cea.cpp
+        PJ_chamb.cpp
+        PJ_collg.cpp
+        PJ_comill.cpp
+        PJ_crast.cpp
+        PJ_deformation.cpp
+        PJ_denoy.cpp
+        PJ_eck1.cpp
+        PJ_eck2.cpp
+        PJ_eck3.cpp
+        PJ_eck4.cpp
+        PJ_eck5.cpp
+        PJ_eqc.cpp
+        PJ_eqdc.cpp
+        PJ_eqearth.cpp
+        PJ_fahey.cpp
+        PJ_fouc_s.cpp
+        PJ_gall.cpp
+        PJ_geoc.cpp
+        PJ_geos.cpp
+        PJ_gins8.cpp
+        PJ_gnom.cpp
+        PJ_gn_sinu.cpp
+        PJ_goode.cpp
+        PJ_gstmerc.cpp
+        PJ_hammer.cpp
+        PJ_hatano.cpp
+        PJ_helmert.cpp
+        PJ_hgridshift.cpp
+        PJ_horner.cpp
+        PJ_igh.cpp
+        PJ_isea.cpp
+        PJ_imw_p.cpp
+        PJ_krovak.cpp
+        PJ_labrd.cpp
+        PJ_laea.cpp
+        PJ_lagrng.cpp
+        PJ_larr.cpp
+        PJ_lask.cpp
+        PJ_latlong.cpp
+        PJ_lcca.cpp
+        PJ_lcc.cpp
+        PJ_loxim.cpp
+        PJ_lsat.cpp
+        PJ_misrsom.cpp
+        PJ_mbt_fps.cpp
+        PJ_mbtfpp.cpp
+        PJ_mbtfpq.cpp
+        PJ_merc.cpp
+        PJ_mill.cpp
+        PJ_mod_ster.cpp
+        PJ_moll.cpp
+        PJ_molodensky.cpp
+        PJ_natearth.cpp
+        PJ_natearth2.cpp
+        PJ_nell.cpp
+        PJ_nell_h.cpp
+        PJ_nocol.cpp
+        PJ_nsper.cpp
+        PJ_nzmg.cpp
+        PJ_ob_tran.cpp
+        PJ_ocea.cpp
+        PJ_oea.cpp
+        PJ_omerc.cpp
+        PJ_ortho.cpp
+        PJ_patterson.cpp
+        PJ_pipeline.cpp
+        PJ_poly.cpp
+        PJ_putp2.cpp
+        PJ_putp3.cpp
+        PJ_putp4p.cpp
+        PJ_putp5.cpp
+        PJ_putp6.cpp
+        PJ_qsc.cpp
+        PJ_robin.cpp
+        PJ_rpoly.cpp
+        PJ_sch.cpp
+        PJ_sconics.cpp
+        PJ_somerc.cpp
+        PJ_sterea.cpp
+        PJ_stere.cpp
+        PJ_sts.cpp
+        PJ_tcc.cpp
+        PJ_tcea.cpp
+        PJ_times.cpp
+        PJ_tmerc.cpp
+        PJ_tobmerc.cpp
+        PJ_tpeqd.cpp
+        PJ_unitconvert.cpp
+        PJ_urm5.cpp
+        PJ_urmfps.cpp
+        PJ_vandg.cpp
+        PJ_vandg2.cpp
+        PJ_vandg4.cpp
+        PJ_vgridshift.cpp
+        PJ_wag2.cpp
+        PJ_wag3.cpp
+        PJ_wag7.cpp
+        PJ_wink1.cpp
+        PJ_wink2.cpp
+        proj_etmerc.cpp
 )
 
 SET(SRC_LIBPROJ_CORE
-        aasincos.c
-        adjlon.c
-        bch2bps.c
-        bchgen.c
-        biveval.c
-        dmstor.c
-        emess.c
+        aasincos.cpp
+        adjlon.cpp
+        bch2bps.cpp
+        bchgen.cpp
+        biveval.cpp
+        dmstor.cpp
+        emess.cpp
         emess.h
-        geocent.c
+        geocent.cpp
         geocent.h
-        geodesic.c
-        mk_cheby.c
-        nad_cvt.c
-        nad_init.c
-        nad_intr.c
-        pj_apply_gridshift.c
-        pj_apply_vgridshift.c
-        pj_auth.c
-        pj_ctx.c
-        pj_fileapi.c
-        pj_datum_set.c
-        pj_datums.c
-        pj_deriv.c
-        pj_ell_set.c
-        pj_ellps.c
-        pj_errno.c
-        pj_factors.c
-        pj_fwd.c
-        pj_gauss.c
-        pj_gc_reader.c
-        pj_geocent.c
-        pj_gridcatalog.c
-        pj_gridinfo.c
-        pj_gridlist.c
-        PJ_healpix.c
-        pj_init.c
-        pj_initcache.c
-        pj_inv.c
-        pj_list.c
+        geodesic.cpp
+        mk_cheby.cpp
+        nad_cvt.cpp
+        nad_init.cpp
+        nad_intr.cpp
+        pj_apply_gridshift.cpp
+        pj_apply_vgridshift.cpp
+        pj_auth.cpp
+        pj_ctx.cpp
+        pj_fileapi.cpp
+        pj_datum_set.cpp
+        pj_datums.cpp
+        pj_deriv.cpp
+        pj_ell_set.cpp
+        pj_ellps.cpp
+        pj_errno.cpp
+        pj_factors.cpp
+        pj_fwd.cpp
+        pj_gauss.cpp
+        pj_gc_reader.cpp
+        pj_geocent.cpp
+        pj_gridcatalog.cpp
+        pj_gridinfo.cpp
+        pj_gridlist.cpp
+        PJ_healpix.cpp
+        pj_init.cpp
+        pj_initcache.cpp
+        pj_inv.cpp
+        pj_list.cpp
         pj_list.h
-        pj_log.c
-        pj_malloc.c
-        pj_math.c
-        pj_mlfn.c
-        pj_msfn.c
-        pj_mutex.c
-        proj_4D_api.c
-        pj_internal.c
+        pj_log.cpp
+        pj_malloc.cpp
+        pj_math.cpp
+        pj_mlfn.cpp
+        pj_msfn.cpp
+        pj_mutex.cpp
+        proj_4D_api.cpp
+        pj_internal.cpp
         proj_internal.h
-        pj_open_lib.c
-        pj_param.c
-        pj_phi2.c
-        pj_pr_list.c
-        pj_qsfn.c
-        pj_release.c
-        pj_strerrno.c
-        pj_transform.c
-        pj_tsfn.c
-        pj_units.c
-        pj_utils.c
-        pj_zpoly1.c
-        proj_mdist.c
+        pj_open_lib.cpp
+        pj_param.cpp
+        pj_phi2.cpp
+        pj_pr_list.cpp
+        pj_qsfn.cpp
+        pj_release.cpp
+        pj_strerrno.cpp
+        pj_transform.cpp
+        pj_tsfn.cpp
+        pj_units.cpp
+        pj_utils.cpp
+        pj_zpoly1.cpp
+        proj_mdist.cpp
         proj_math.h
-        proj_rouss.c
-        rtodms.c
-        vector1.c
-        pj_strtod.c
+        proj_rouss.cpp
+        rtodms.cpp
+        vector1.cpp
+        pj_strtod.cpp
         pj_wkt1_generated_parser.c
         pj_wkt2_generated_parser.c
         ${CMAKE_CURRENT_BINARY_DIR}/proj_config.h
@@ -301,7 +301,7 @@ endif(JNI_SUPPORT AND NOT JNI_FOUND)
 boost_report_value(JNI_SUPPORT)
 if(JNI_SUPPORT)
   set(SRC_LIBPROJ_CORE ${SRC_LIBPROJ_CORE}
-                       jniproj.c )
+                       jniproj.cpp )
   set(HEADERS_LIBPROJ ${HEADERS_LIBPROJ}
                         org_proj4_PJ.h)
   source_group("Source Files\\JNI" FILES ${SRC_LIBPROJ_JNI})
diff --git a/src/mk_cheby.c b/src/mk_cheby.cpp
index a2f90bef..a2f90bef 100644
--- a/src/mk_cheby.c
+++ b/src/mk_cheby.cpp
diff --git a/src/multistresstest.c b/src/multistresstest.cpp
index b0bd5c9c..a6653e7e 100644
--- a/src/multistresstest.c
+++ b/src/multistresstest.cpp
@@ -177,7 +177,7 @@ static TestItem test_list[] = {
 
 static volatile int active_thread_count = 0;
 
-static projPJ* custom_pj_init_plus_ctx(projCtx ctx, const char* def)
+static projPJ custom_pj_init_plus_ctx(projCtx ctx, const char* def)
 {
     if( add_no_defs )
     {
diff --git a/src/nad2bin.c b/src/nad2bin.cpp
index eb8672a5..eb8672a5 100644
--- a/src/nad2bin.c
+++ b/src/nad2bin.cpp
diff --git a/src/nad_cvt.c b/src/nad_cvt.cpp
index ec4a2b47..ec4a2b47 100644
--- a/src/nad_cvt.c
+++ b/src/nad_cvt.cpp
diff --git a/src/nad_init.c b/src/nad_init.cpp
index 8b024ac7..8b024ac7 100644
--- a/src/nad_init.c
+++ b/src/nad_init.cpp
diff --git a/src/nad_intr.c b/src/nad_intr.cpp
index 1f9d1e0c..1f9d1e0c 100644
--- a/src/nad_intr.c
+++ b/src/nad_intr.cpp
diff --git a/src/p_series.c b/src/p_series.cpp
index cddea888..cddea888 100644
--- a/src/p_series.c
+++ b/src/p_series.cpp
diff --git a/src/pj_apply_gridshift.c b/src/pj_apply_gridshift.cpp
index 45ce5c8e..45ce5c8e 100644
--- a/src/pj_apply_gridshift.c
+++ b/src/pj_apply_gridshift.cpp
diff --git a/src/pj_apply_vgridshift.c b/src/pj_apply_vgridshift.cpp
index c1344951..c1344951 100644
--- a/src/pj_apply_vgridshift.c
+++ b/src/pj_apply_vgridshift.cpp
diff --git a/src/pj_auth.c b/src/pj_auth.cpp
index d6024671..d6024671 100644
--- a/src/pj_auth.c
+++ b/src/pj_auth.cpp
diff --git a/src/pj_ctx.c b/src/pj_ctx.cpp
index 1c99e921..1c99e921 100644
--- a/src/pj_ctx.c
+++ b/src/pj_ctx.cpp
diff --git a/src/pj_datum_set.c b/src/pj_datum_set.cpp
index 466b56c5..466b56c5 100644
--- a/src/pj_datum_set.c
+++ b/src/pj_datum_set.cpp
diff --git a/src/pj_datums.c b/src/pj_datums.cpp
index 2951b7bd..2951b7bd 100644
--- a/src/pj_datums.c
+++ b/src/pj_datums.cpp
diff --git a/src/pj_deriv.c b/src/pj_deriv.cpp
index 2c91e0cc..2c91e0cc 100644
--- a/src/pj_deriv.c
+++ b/src/pj_deriv.cpp
diff --git a/src/pj_ell_set.c b/src/pj_ell_set.cpp
index e2d2750c..e2d2750c 100644
--- a/src/pj_ell_set.c
+++ b/src/pj_ell_set.cpp
diff --git a/src/pj_ellps.c b/src/pj_ellps.cpp
index 8b3b8f0a..8b3b8f0a 100644
--- a/src/pj_ellps.c
+++ b/src/pj_ellps.cpp
diff --git a/src/pj_errno.c b/src/pj_errno.cpp
index 6e98cd73..6e98cd73 100644
--- a/src/pj_errno.c
+++ b/src/pj_errno.cpp
diff --git a/src/pj_factors.c b/src/pj_factors.cpp
index e4b871a1..e4b871a1 100644
--- a/src/pj_factors.c
+++ b/src/pj_factors.cpp
diff --git a/src/pj_fileapi.c b/src/pj_fileapi.cpp
index eba96afd..eba96afd 100644
--- a/src/pj_fileapi.c
+++ b/src/pj_fileapi.cpp
diff --git a/src/pj_fwd.c b/src/pj_fwd.cpp
index 38443f07..38443f07 100644
--- a/src/pj_fwd.c
+++ b/src/pj_fwd.cpp
diff --git a/src/pj_gauss.c b/src/pj_gauss.cpp
index 4520bb39..4520bb39 100644
--- a/src/pj_gauss.c
+++ b/src/pj_gauss.cpp
diff --git a/src/pj_gc_reader.c b/src/pj_gc_reader.cpp
index 493fc075..493fc075 100644
--- a/src/pj_gc_reader.c
+++ b/src/pj_gc_reader.cpp
diff --git a/src/pj_geocent.c b/src/pj_geocent.cpp
index 0e9d725e..0e9d725e 100644
--- a/src/pj_geocent.c
+++ b/src/pj_geocent.cpp
diff --git a/src/pj_gridcatalog.c b/src/pj_gridcatalog.cpp
index ea9c4aa1..ea9c4aa1 100644
--- a/src/pj_gridcatalog.c
+++ b/src/pj_gridcatalog.cpp
diff --git a/src/pj_gridinfo.c b/src/pj_gridinfo.cpp
index de0e8d31..de0e8d31 100644
--- a/src/pj_gridinfo.c
+++ b/src/pj_gridinfo.cpp
diff --git a/src/pj_gridlist.c b/src/pj_gridlist.cpp
index 332de8dd..332de8dd 100644
--- a/src/pj_gridlist.c
+++ b/src/pj_gridlist.cpp
diff --git a/src/pj_init.c b/src/pj_init.cpp
index 36a3276f..b09d70ed 100644
--- a/src/pj_init.c
+++ b/src/pj_init.cpp
@@ -61,8 +61,10 @@ static paralist *string_to_paralist (PJ_CONTEXT *ctx, char *definition) {
             first = next = pj_mkparam_ws (c);
         else
             next = next->next = pj_mkparam_ws (c);
-        if (0==next)
-            return pj_dealloc_params (ctx, first, ENOMEM);
+        if (0==next) {
+            pj_dealloc_params (ctx, first, ENOMEM);
+            return nullptr;
+        }
 
         /* And skip to the end of the substring */
         while ((!isspace(*c)) && 0!=*c)
@@ -95,11 +97,11 @@ static char *get_init_string (PJ_CONTEXT *ctx, const char *name) {
     size_t n;
 
 
-    line = pj_malloc (MAX_LINE_LENGTH + 1);
+    line = static_cast<char*>(pj_malloc (MAX_LINE_LENGTH + 1));
     if (0==line)
         return 0;
 
-    fname = pj_malloc (MAX_PATH_FILENAME+ID_TAG_MAX+3);
+    fname = static_cast<char*>(pj_malloc (MAX_PATH_FILENAME+ID_TAG_MAX+3));
     if (0==fname) {
         pj_dealloc (line);
         return 0;
@@ -167,7 +169,7 @@ static char *get_init_string (PJ_CONTEXT *ctx, const char *name) {
     }
 
     /* We're at the first line of the right section - copy line to buffer */
-    buffer = pj_malloc (current_buffer_size);
+    buffer = static_cast<char*>(pj_malloc (current_buffer_size));
     if (0==buffer) {
         pj_dealloc (fname);
         pj_dealloc (line);
@@ -200,7 +202,7 @@ static char *get_init_string (PJ_CONTEXT *ctx, const char *name) {
         pj_chomp (line);   /* Remove '#' style comments */
         next_length = strlen (line) + buffer_length + 2;
         if (next_length > current_buffer_size) {
-            char *b = pj_malloc (2 * current_buffer_size);
+            char *b = static_cast<char*>(pj_malloc (2 * current_buffer_size));
             if (0==b) {
                 pj_dealloc (buffer);
                 buffer = 0;
@@ -611,13 +613,17 @@ pj_init_ctx_with_allow_init_epsg(projCtx ctx, int argc, char **argv, int allow_i
 
     /* put arguments into internal linked list */
     start = curr = pj_mkparam(argv[0]);
-    if (!curr)
-        return pj_dealloc_params (ctx, start, ENOMEM);
+    if (!curr) {
+        pj_dealloc_params (ctx, start, ENOMEM);
+        return nullptr;
+    }
 
     for (i = 1; i < argc; ++i) {
         curr->next = pj_mkparam(argv[i]);
-        if (!curr->next)
-            return pj_dealloc_params (ctx, start, ENOMEM);
+        if (!curr->next) {
+            pj_dealloc_params (ctx, start, ENOMEM);
+            return nullptr;
+        }
         curr = curr->next;
     }
 
@@ -629,24 +635,34 @@ pj_init_ctx_with_allow_init_epsg(projCtx ctx, int argc, char **argv, int allow_i
     init = pj_param_exists (start, "init");
     if (init && n_pipelines == 0) {
         init = pj_expand_init_internal (ctx, init, allow_init_epsg);
-        if (!init)
-            return pj_dealloc_params (ctx, start, PJD_ERR_NO_ARGS);
+        if (!init) {
+            pj_dealloc_params (ctx, start, PJD_ERR_NO_ARGS);
+            return nullptr;
+        }
+    }
+    if (ctx->last_errno) {
+        pj_dealloc_params (ctx, start, ctx->last_errno);
+        return nullptr;
     }
-    if (ctx->last_errno)
-        return pj_dealloc_params (ctx, start, ctx->last_errno);
 
     /* Find projection selection */
     curr = pj_param_exists (start, "proj");
-    if (0==curr)
-        return pj_dealloc_params (ctx, start, PJD_ERR_PROJ_NOT_NAMED);
+    if (0==curr) {
+        pj_dealloc_params (ctx, start, PJD_ERR_PROJ_NOT_NAMED);
+        return nullptr;
+    }
     name =  curr->param;
-    if (strlen (name) < 6)
-        return pj_dealloc_params (ctx, start, PJD_ERR_PROJ_NOT_NAMED);
+    if (strlen (name) < 6) {
+        pj_dealloc_params (ctx, start, PJD_ERR_PROJ_NOT_NAMED);
+        return nullptr;
+    }
     name += 5;
 
     proj = locate_constructor (name);
-    if (0==proj)
-        return pj_dealloc_params (ctx, start, PJD_ERR_UNKNOWN_PROJECTION_ID);
+    if (0==proj) {
+        pj_dealloc_params (ctx, start, PJD_ERR_UNKNOWN_PROJECTION_ID);
+        return nullptr;
+    }
 
 
     /* Append general and projection specific defaults to the definition list */
@@ -656,8 +672,10 @@ pj_init_ctx_with_allow_init_epsg(projCtx ctx, int argc, char **argv, int allow_i
 
     /* Allocate projection structure */
     PIN = proj(0);
-    if (0==PIN)
-        return pj_dealloc_params (ctx, start, ENOMEM);
+    if (0==PIN) {
+        pj_dealloc_params (ctx, start, ENOMEM);
+        return nullptr;
+    }
 
 
     PIN->ctx = ctx;
@@ -853,7 +871,7 @@ pj_init_ctx_with_allow_init_epsg(projCtx ctx, int argc, char **argv, int allow_i
         PIN->from_greenwich = 0.0;
 
     /* Private object for the geodesic functions */
-    PIN->geod = pj_calloc (1, sizeof (struct geod_geodesic));
+    PIN->geod = static_cast<struct geod_geodesic*>(pj_calloc (1, sizeof (struct geod_geodesic)));
     if (0==PIN->geod)
         return pj_default_destructor (PIN, ENOMEM);
     geod_init(PIN->geod, PIN->a,  (1 - sqrt (1 - PIN->es)));
diff --git a/src/pj_initcache.c b/src/pj_initcache.cpp
index 3c347e4b..3c347e4b 100644
--- a/src/pj_initcache.c
+++ b/src/pj_initcache.cpp
diff --git a/src/pj_internal.c b/src/pj_internal.cpp
index 7eb917be..ac9fe1e0 100644
--- a/src/pj_internal.c
+++ b/src/pj_internal.cpp
@@ -76,7 +76,7 @@ chained calls starting out with a call to its 2D interface.
     if (0==P)
         return coo;
     if (P->inverted)
-        direction = -direction;
+        direction = static_cast<PJ_DIRECTION>(-direction);
     switch (direction) {
         case PJ_FWD:
             coo.xy = pj_fwd (coo.lp, P);
@@ -106,7 +106,7 @@ chained calls starting out with a call to its 3D interface.
     if (0==P)
         return coo;
     if (P->inverted)
-        direction = -direction;
+        direction = static_cast<PJ_DIRECTION>(-direction);
     switch (direction) {
         case PJ_FWD:
             coo.xyz = pj_fwd3d (coo.lpz, P);
@@ -343,7 +343,7 @@ array.
     for (i = n = 0;  i < argc;  i++)
         n += strlen (argv[i]);
 
-    p = pj_calloc (n + argc + 1, sizeof (char));
+    p = static_cast<char*>(pj_calloc (n + argc + 1, sizeof (char)));
     if (0==p)
         return 0;
     if (0==argc)
@@ -385,7 +385,7 @@ PJ_LOG_LEVEL proj_log_level (PJ_CONTEXT *ctx, PJ_LOG_LEVEL log_level) {
         ctx = pj_get_default_ctx();
     if (0==ctx)
         return PJ_LOG_TELL;
-    previous = abs (ctx->debug_level);
+    previous = static_cast<PJ_LOG_LEVEL>(abs (ctx->debug_level));
     if (PJ_LOG_TELL==log_level)
         return previous;
     ctx->debug_level = log_level;
diff --git a/src/pj_inv.c b/src/pj_inv.cpp
index aaa8fea9..aaa8fea9 100644
--- a/src/pj_inv.c
+++ b/src/pj_inv.cpp
diff --git a/src/pj_list.c b/src/pj_list.cpp
index 33313875..55ea36c2 100644
--- a/src/pj_list.c
+++ b/src/pj_list.cpp
@@ -9,12 +9,12 @@
 
 
 /* Generate prototypes for projection functions */
-#define PROJ_HEAD(id, name) struct PJconsts *pj_##id(struct PJconsts*);
+#define PROJ_HEAD(id, name) extern "C" struct PJconsts *pj_##id(struct PJconsts*);
 #include "pj_list.h"
 #undef PROJ_HEAD
 
 /* Generate extern declarations for description strings */
-#define PROJ_HEAD(id, name) extern const char * const pj_s_##id;
+#define PROJ_HEAD(id, name) extern "C" const char * const pj_s_##id;
 #include "pj_list.h"
 #undef PROJ_HEAD
 
diff --git a/src/pj_log.c b/src/pj_log.cpp
index 6654691c..6654691c 100644
--- a/src/pj_log.c
+++ b/src/pj_log.cpp
diff --git a/src/pj_malloc.c b/src/pj_malloc.cpp
index c45da85d..66977cf4 100644
--- a/src/pj_malloc.c
+++ b/src/pj_malloc.cpp
@@ -139,7 +139,7 @@ char *pj_strdup(const char *str)
 /**********************************************************************/
 {
     size_t len = strlen(str) + 1;
-    char *dup = pj_malloc(len);
+    char *dup = static_cast<char*>(pj_malloc(len));
     if (dup)
         memcpy(dup, str, len);
     return dup;
@@ -192,7 +192,7 @@ void pj_free(PJ *P) {
 
 
 /*****************************************************************************/
-void *pj_default_destructor (PJ *P, int errlev) {   /* Destructor */
+PJ *pj_default_destructor (PJ *P, int errlev) {   /* Destructor */
 /*****************************************************************************
     Does memory deallocation for "plain" PJ objects, i.e. that vast majority
     of PJs where the opaque object does not contain any additionally
@@ -234,6 +234,7 @@ void *pj_default_destructor (PJ *P, int errlev) {   /* Destructor */
     pj_free (P->hgridshift);
     pj_free (P->vgridshift);
 
-    pj_dealloc (P->opaque);
-    return pj_dealloc(P);
+    pj_dealloc (static_cast<struct pj_opaque*>(P->opaque));
+    pj_dealloc(P);
+    return nullptr;
 }
diff --git a/src/pj_math.c b/src/pj_math.cpp
index 540ab9eb..540ab9eb 100644
--- a/src/pj_math.c
+++ b/src/pj_math.cpp
diff --git a/src/pj_mlfn.c b/src/pj_mlfn.cpp
index 02e05c3a..02e05c3a 100644
--- a/src/pj_mlfn.c
+++ b/src/pj_mlfn.cpp
diff --git a/src/pj_msfn.c b/src/pj_msfn.cpp
index 999e73a7..999e73a7 100644
--- a/src/pj_msfn.c
+++ b/src/pj_msfn.cpp
diff --git a/src/pj_mutex.c b/src/pj_mutex.cpp
index dc4a441b..dc4a441b 100644
--- a/src/pj_mutex.c
+++ b/src/pj_mutex.cpp
diff --git a/src/pj_open_lib.c b/src/pj_open_lib.cpp
index 6b908360..31a2c2e1 100644
--- a/src/pj_open_lib.c
+++ b/src/pj_open_lib.cpp
@@ -84,10 +84,10 @@ void pj_set_searchpath ( int count, const char **path )
 
     if( count > 0 )
     {
-        search_path = pj_malloc(sizeof *search_path * count);
+        search_path = static_cast<char**>(pj_malloc(sizeof *search_path * count));
         for (i = 0; i < count; i++)
         {
-            search_path[i] = pj_malloc(strlen(path[i]) + 1);
+            search_path[i] = static_cast<char*>(pj_malloc(strlen(path[i]) + 1));
             strcpy(search_path[i], path[i]);
         }
     }
diff --git a/src/pj_param.c b/src/pj_param.cpp
index 4078dc83..1887afe9 100644
--- a/src/pj_param.c
+++ b/src/pj_param.cpp
@@ -70,7 +70,7 @@ paralist *pj_param_exists (paralist *list, const char *parameter) {
     the t (for compile time known names, this is obviously not an issue).
 ***************************************************************************************/
     paralist *next = list;
-    char *c = strchr (parameter, '=');
+    const char *c = strchr (parameter, '=');
     size_t len = strlen (parameter);
     if (c)
         len = c - parameter;
diff --git a/src/pj_phi2.c b/src/pj_phi2.cpp
index a83302e6..a83302e6 100644
--- a/src/pj_phi2.c
+++ b/src/pj_phi2.cpp
diff --git a/src/pj_pr_list.c b/src/pj_pr_list.cpp
index 4e71e471..4e71e471 100644
--- a/src/pj_pr_list.c
+++ b/src/pj_pr_list.cpp
diff --git a/src/pj_qsfn.c b/src/pj_qsfn.cpp
index c18a7b95..c18a7b95 100644
--- a/src/pj_qsfn.c
+++ b/src/pj_qsfn.cpp
diff --git a/src/pj_release.c b/src/pj_release.cpp
index 9beb45ef..9beb45ef 100644
--- a/src/pj_release.c
+++ b/src/pj_release.cpp
diff --git a/src/pj_strerrno.c b/src/pj_strerrno.cpp
index 16042f79..16042f79 100644
--- a/src/pj_strerrno.c
+++ b/src/pj_strerrno.cpp
diff --git a/src/pj_strtod.c b/src/pj_strtod.cpp
index f604a013..f604a013 100644
--- a/src/pj_strtod.c
+++ b/src/pj_strtod.cpp
diff --git a/src/pj_transform.c b/src/pj_transform.cpp
index 6982676e..53429967 100644
--- a/src/pj_transform.c
+++ b/src/pj_transform.cpp
@@ -45,7 +45,7 @@ enum PJ_DIRECTION {
 typedef enum PJ_DIRECTION PJ_DIRECTION;
 
 /* Copied from proj.h FIXME */
-int  proj_errno_reset (const PJ *P);
+extern "C" int  proj_errno_reset (const PJ *P);
 
 
 static int adjust_axis( projCtx ctx, const char *axis, int denormalize_flag,
diff --git a/src/pj_tsfn.c b/src/pj_tsfn.cpp
index ea3b896d..ea3b896d 100644
--- a/src/pj_tsfn.c
+++ b/src/pj_tsfn.cpp
diff --git a/src/pj_units.c b/src/pj_units.cpp
index 877758a3..877758a3 100644
--- a/src/pj_units.c
+++ b/src/pj_units.cpp
diff --git a/src/pj_utils.c b/src/pj_utils.cpp
index 81a80b45..81a80b45 100644
--- a/src/pj_utils.c
+++ b/src/pj_utils.cpp
diff --git a/src/pj_zpoly1.c b/src/pj_zpoly1.cpp
index bacb62ce..bacb62ce 100644
--- a/src/pj_zpoly1.c
+++ b/src/pj_zpoly1.cpp
diff --git a/src/proj.c b/src/proj.cpp
index 2405781c..2405781c 100644
--- a/src/proj.c
+++ b/src/proj.cpp
diff --git a/src/proj_4D_api.c b/src/proj_4D_api.cpp
index 75a061a0..c2a37a49 100644
--- a/src/proj_4D_api.c
+++ b/src/proj_4D_api.cpp
@@ -53,6 +53,10 @@ PJ_COORD proj_coord (double x, double y, double z, double t) {
     return res;
 }
 
+static PJ_DIRECTION opposite_direction(PJ_DIRECTION dir) {
+    return static_cast<PJ_DIRECTION>(-dir);
+}
+
 /*****************************************************************************/
 int proj_angular_input (PJ *P, enum PJ_DIRECTION dir) {
 /******************************************************************************
@@ -72,7 +76,7 @@ int proj_angular_output (PJ *P, enum PJ_DIRECTION dir) {
     operating in direction dir, 0 otherwise.
     dir: {PJ_FWD, PJ_INV}
 ******************************************************************************/
-    return proj_angular_input (P, -dir);
+    return proj_angular_input (P, opposite_direction(dir));
 }
 
 
@@ -142,10 +146,10 @@ double proj_roundtrip (PJ *P, PJ_DIRECTION direction, int n, PJ_COORD *coord) {
     /* now we take n-1 full steps in inverse direction: We are */
     /* out of phase due to the half step already taken */
     for (i = 0;  i < n - 1;  i++)
-        t = proj_trans (P,  direction,  proj_trans (P, -direction, t) );
+        t = proj_trans (P,  direction,  proj_trans (P, opposite_direction(direction), t) );
 
     /* finally, we take the last half-step */
-    t = proj_trans (P, -direction, t);
+    t = proj_trans (P, opposite_direction(direction), t);
 
     /* checking for angular *input* since we do a roundtrip, and end where we begin */
     if (proj_angular_input (P, direction))
@@ -168,7 +172,7 @@ similarly, but prefers the 2D resp. 3D interfaces if available.
     if (0==P)
         return coord;
     if (P->inverted)
-        direction = -direction;
+        direction = opposite_direction(direction);
 
     switch (direction) {
         case PJ_FWD:
@@ -274,7 +278,7 @@ size_t proj_trans_generic (
         return 0;
 
     if (P->inverted)
-        direction = -direction;
+        direction = opposite_direction(direction);
 
     /* ignore lengths of null arrays */
     if (0==x) nx = 0;
@@ -441,7 +445,7 @@ Returns 1 on success, 0 on failure
 
     /* Don't axisswap if data are already in "enu" order */
     if (p && (0!=strcmp ("enu", p->param))) {
-        char *def = malloc (100+strlen(P->axis));
+        char *def = static_cast<char*>(malloc (100+strlen(P->axis)));
         if (0==def)
             return 0;
         sprintf (def, "break_cs2cs_recursion     proj=axisswap  axis=%s", P->axis);
@@ -456,7 +460,7 @@ Returns 1 on success, 0 on failure
     p = pj_param_exists (P->params, "geoidgrids");
     if (p  &&  strlen (p->param) > strlen ("geoidgrids=")) {
         char *gridnames = p->param + strlen ("geoidgrids=");
-        char *def = malloc (100+strlen(gridnames));
+        char *def = static_cast<char*>(malloc (100+strlen(gridnames)));
         if (0==def)
             return 0;
         sprintf (def, "break_cs2cs_recursion     proj=vgridshift  grids=%s", gridnames);
@@ -471,7 +475,7 @@ Returns 1 on success, 0 on failure
     p = pj_param_exists (P->params, "nadgrids");
     if (p  &&  strlen (p->param) > strlen ("nadgrids=")) {
         char *gridnames = p->param + strlen ("nadgrids=");
-        char *def = malloc (100+strlen(gridnames));
+        char *def = static_cast<char*>(malloc (100+strlen(gridnames)));
         if (0==def)
             return 0;
         sprintf (def, "break_cs2cs_recursion     proj=hgridshift  grids=%s", gridnames);
@@ -503,7 +507,7 @@ Returns 1 on success, 0 on failure
         if (n <= 8) /* 8==strlen ("towgs84=") */
             return 0;
 
-        def = malloc (100+n);
+        def = static_cast<char*>(malloc (100+n));
         if (0==def)
             return 0;
         sprintf (def, "break_cs2cs_recursion     proj=helmert exact %s convention=position_vector", s);
@@ -642,7 +646,7 @@ indicator, as in {"+proj=utm", "+zone=32"}, or leave it out, as in {"proj=utm",
 
 /** Create an area of use */
 PJ_AREA * proj_area_create(void) {
-    return pj_calloc(1, sizeof(PJ_AREA));
+    return static_cast<PJ_AREA*>(pj_calloc(1, sizeof(PJ_AREA)));
 }
 
 /** Assign a bounding box to an area of use. */
@@ -967,7 +971,7 @@ static char *path_append (char *buf, const char *app, size_t *buf_size) {
 
     /* "pj_realloc", so to speak */
     if (*buf_size < len) {
-        p = pj_calloc (2 * len, sizeof (char));
+        p = static_cast<char*>(pj_calloc (2 * len, sizeof (char)));
         if (0==p) {
             pj_dealloc (buf);
             return 0;
diff --git a/src/proj_etmerc.c b/src/proj_etmerc.cpp
index 4d7187e6..0ba710d7 100644
--- a/src/proj_etmerc.c
+++ b/src/proj_etmerc.cpp
@@ -145,7 +145,7 @@ static double clens(double *a, int size, double arg_r) {
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double sin_Cn, cos_Cn, cos_Ce, sin_Ce, dCn, dCe;
     double Cn = lp.phi, Ce = lp.lam;
 
@@ -181,7 +181,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double sin_Cn, cos_Cn, cos_Ce, sin_Ce, dCn, dCe;
     double Cn = xy.y, Ce = xy.x;
 
@@ -218,7 +218,7 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 
 static PJ *setup(PJ *P) { /* general initialization */
     double f, n, np, Z;
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
 
     if (P->es <= 0) {
         return pj_default_destructor(P, PJD_ERR_ELLIPSOID_USE_REQUIRED);
@@ -306,7 +306,7 @@ static PJ *setup(PJ *P) { /* general initialization */
 
 
 PJ *PROJECTION(etmerc) {
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
@@ -320,7 +320,7 @@ PJ *PROJECTION(etmerc) {
 
 PJ *PROJECTION(utm) {
     long zone;
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor (P, ENOMEM);
     P->opaque = Q;
diff --git a/src/proj_mdist.c b/src/proj_mdist.cpp
index 777f704d..777f704d 100644
--- a/src/proj_mdist.c
+++ b/src/proj_mdist.cpp
diff --git a/src/proj_rouss.c b/src/proj_rouss.cpp
index 0e0f9982..f39e0a15 100644
--- a/src/proj_rouss.c
+++ b/src/proj_rouss.cpp
@@ -44,7 +44,7 @@ PROJ_HEAD(rouss, "Roussilhe Stereographic") "\n\tAzi, Ell";
 
 static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
     XY xy = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double s, al, cp, sp, al2, s2;
 
     cp = cos(lp.phi);
@@ -65,7 +65,7 @@ static XY e_forward (LP lp, PJ *P) {          /* Ellipsoidal, forward */
 
 static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
     LP lp = {0.0,0.0};
-    struct pj_opaque *Q = P->opaque;
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque);
     double s, al, x = xy.x / P->k0, y = xy.y / P->k0, x2, y2;;
 
     x2 = x * x;
@@ -83,15 +83,15 @@ static LP e_inverse (XY xy, PJ *P) {          /* Ellipsoidal, inverse */
 }
 
 
-static void *destructor (PJ *P, int errlev) {
+static PJ *destructor (PJ *P, int errlev) {
     if (0==P)
         return 0;
 
     if (0==P->opaque)
         return pj_default_destructor (P, errlev);
 
-    if (P->opaque->en)
-        pj_dealloc (P->opaque->en);
+    if (static_cast<struct pj_opaque*>(P->opaque)->en)
+        pj_dealloc (static_cast<struct pj_opaque*>(P->opaque)->en);
 
     return pj_default_destructor (P, ENOMEM);
 }
@@ -100,7 +100,7 @@ static void *destructor (PJ *P, int errlev) {
 PJ *PROJECTION(rouss) {
     double N0, es2, t, t2, R_R0_2, R_R0_4;
 
-    struct pj_opaque *Q = pj_calloc (1, sizeof (struct pj_opaque));
+    struct pj_opaque *Q = static_cast<struct pj_opaque*>(pj_calloc (1, sizeof (struct pj_opaque)));
     if (0==Q)
         return pj_default_destructor(P, ENOMEM);
     P->opaque = Q;
diff --git a/src/proj_strtod.c b/src/proj_strtod.cpp
index a3bc7d40..05d448ec 100644
--- a/src/proj_strtod.c
+++ b/src/proj_strtod.cpp
@@ -315,7 +315,7 @@ double proj_strtod(const char *str, char **endptr) {
 }
 
 double proj_atof(const char *str) {
-    return proj_strtod(str, (void *) 0);
+    return proj_strtod(str, nullptr);
 }
 
 #ifdef TEST
diff --git a/src/projects.h b/src/projects.h
index 11467d56..ac1a2152 100644
--- a/src/projects.h
+++ b/src/projects.h
@@ -197,7 +197,6 @@ struct PJconsts;
 
 union  PJ_COORD;
 struct geod_geodesic;
-struct pj_opaque;
 struct ARG_list;
 struct PJ_REGION_S;
 typedef struct PJ_REGION_S  PJ_Region;
@@ -260,7 +259,7 @@ PJ_OPERATOR:
 
 *****************************************************************************/
 typedef    PJ       *(* PJ_CONSTRUCTOR) (PJ *);
-typedef    void     *(* PJ_DESTRUCTOR)  (PJ *, int);
+typedef    PJ       *(* PJ_DESTRUCTOR)  (PJ *, int);
 typedef    PJ_COORD  (* PJ_OPERATOR)    (PJ_COORD, PJ *);
 /****************************************************************************/
 
@@ -290,7 +289,7 @@ struct PJconsts {
     char *def_ellps;
 
     struct geod_geodesic *geod;    /* For geodesic computations */
-    struct pj_opaque *opaque;      /* Projection specific parameters, Defined in PJ_*.c */
+    void *opaque;      /* Projection specific parameters, Defined in PJ_*.c */
     int inverted;                  /* Tell high level API functions to swap inv/fwd */
 
 
@@ -828,7 +827,7 @@ extern char const PROJ_DLL pj_release[];
 
 struct PJ_DATUMS           PROJ_DLL *pj_get_datums_ref( void );
 
-void *pj_default_destructor (PJ *P, int errlev);
+PJ *pj_default_destructor (PJ *P, int errlev);
 
 double PROJ_DLL pj_atof( const char* nptr );
 double pj_strtod( const char *nptr, char **endptr );
diff --git a/src/rtodms.c b/src/rtodms.cpp
index 674cebdf..674cebdf 100644
--- a/src/rtodms.c
+++ b/src/rtodms.cpp
diff --git a/src/test228.c b/src/test228.cpp
index 83d29f8f..83d29f8f 100644
--- a/src/test228.c
+++ b/src/test228.cpp
diff --git a/src/vector1.c b/src/vector1.cpp
index 22e1f5d0..22e1f5d0 100644
--- a/src/vector1.c
+++ b/src/vector1.cpp