Fix some issues raised by latest cppcheck

- coordinateoperation_internal.hpp: missing 'explicit' keyword
- proj.cpp: unused 'generic' member in enumeration
- init.cpp: useless assignment to a_orig and es_orig, because done again a
            few lines below.
- crs.cpp: unused variable
- datum.cpp: inefficient use of find() function
- io.cpp:
  * missing 'static' qualifier for method
  * useles ternary test (left and right have same value)
- aeqd.cpp: useless assignment of inv and fwd, snice done again a few lines
            below
- isea.cpp: useless assignment of resolution and aperture since done again a
            few lines below, and with default values when params are absent
- mod_ster.cpp: useless assignment of lp.lam, overriden in below code paths.
- stere.cpp: false positive, but better not modify another variable than the
             iterator in a for() loop.

4 files changed, 2 insertions, 11 deletions

diff --git a/src/projections/aeqd.cpp b/src/projections/aeqd.cpp
index 8566062d..882d9531 100644
--- a/src/projections/aeqd.cpp
+++ b/src/projections/aeqd.cpp
@@ -310,7 +310,6 @@ PJ *PROJECTION(aeqd) {
                 break;
             case EQUIT:
             case OBLIQ:
-                P->inv = e_inverse; P->fwd = e_forward;
                 Q->N1 = 1. / sqrt(1. - P->es * Q->sinph0 * Q->sinph0);
                 Q->G = Q->sinph0 * (Q->He = P->e / sqrt(P->one_es));
                 Q->He *= Q->cosph0;
diff --git a/src/projections/isea.cpp b/src/projections/isea.cpp
index d53317c1..fc74bebe 100644
--- a/src/projections/isea.cpp
+++ b/src/projections/isea.cpp
@@ -1051,14 +1051,6 @@ PJ *PROJECTION(isea) {
         Q->dgg.o_lat = pj_param(P->ctx,P->params, "rlat_0").f;
     }
 
-    if (pj_param(P->ctx,P->params, "taperture").i) {
-        Q->dgg.aperture = pj_param(P->ctx,P->params, "iaperture").i;
-    }
-
-    if (pj_param(P->ctx,P->params, "tresolution").i) {
-        Q->dgg.resolution = pj_param(P->ctx,P->params, "iresolution").i;
-    }
-
     opt = pj_param(P->ctx,P->params, "smode").s;
     if (opt) {
         if (!strcmp(opt, "plane")) {
diff --git a/src/projections/mod_ster.cpp b/src/projections/mod_ster.cpp
index 83390178..b26ea289 100644
--- a/src/projections/mod_ster.cpp
+++ b/src/projections/mod_ster.cpp
@@ -72,7 +72,6 @@ static PJ_LP e_inverse (PJ_XY xy, PJ *P) {          /* Ellipsoidal, inverse */
         z = 2. * atan(.5 * rh);
         sinz = sin(z);
         cosz = cos(z);
-        lp.lam = P->lam0;
         if (fabs(rh) <= EPSLN) {
             /* if we end up here input coordinates were (0,0).
              * pj_inv() adds P->lam0 to lp.lam, this way we are
diff --git a/src/projections/stere.cpp b/src/projections/stere.cpp
index 9b24a596..9836f341 100644
--- a/src/projections/stere.cpp
+++ b/src/projections/stere.cpp
@@ -165,7 +165,7 @@ static PJ_LP e_inverse (PJ_XY xy, PJ *P) {          /* Ellipsoidal, inverse */
         break;
     }
 
-    for (i = NITER;  i--;  phi_l = lp.phi) {
+    for (i = NITER;  i--; ) {
         sinphi = P->e * sin(phi_l);
         lp.phi = 2. * atan (tp * pow ((1.+sinphi)/(1.-sinphi), halfe)) - halfpi;
         if (fabs (phi_l - lp.phi) < CONV) {
@@ -174,6 +174,7 @@ static PJ_LP e_inverse (PJ_XY xy, PJ *P) {          /* Ellipsoidal, inverse */
             lp.lam = (xy.x == 0. && xy.y == 0.) ? 0. : atan2 (xy.x, xy.y);
             return lp;
         }
+        phi_l = lp.phi;
     }
 
     proj_errno_set(P, PJD_ERR_TOLERANCE_CONDITION);