3 files changed, 16 insertions, 0 deletions
diff --git a/src/4D_api.cpp b/src/4D_api.cpp
index 88210348..de950c7a 100644
--- a/src/4D_api.cpp
+++ b/src/4D_api.cpp
@@ -757,11 +757,13 @@ PJ  *proj_create_crs_to_crs (PJ_CONTEXT *ctx, const char *source_crs, const char
 
     src = proj_obj_create_from_user_input(ctx, source_crs, optionsImportCRS);
     if( !src ) {
+        proj_context_log_debug(ctx, "Cannot instanciate source_crs");
         return nullptr;
     }
 
     dst = proj_obj_create_from_user_input(ctx, target_crs, optionsImportCRS);
     if( !dst ) {
+        proj_context_log_debug(ctx, "Cannot instanciate target_crs");
         proj_obj_destroy(src);
         return nullptr;
     }
@@ -798,6 +800,7 @@ PJ  *proj_create_crs_to_crs (PJ_CONTEXT *ctx, const char *source_crs, const char
 
     if( proj_obj_list_get_count(op_list) == 0 ) {
         proj_obj_list_destroy(op_list);
+        proj_context_log_debug(ctx, "No operation found matching criteria");
         return nullptr;
     }
 
@@ -810,6 +813,7 @@ PJ  *proj_create_crs_to_crs (PJ_CONTEXT *ctx, const char *source_crs, const char
     proj_string = proj_obj_as_proj_string(ctx, op, PJ_PROJ_5, nullptr);
     if( !proj_string) {
         proj_obj_destroy(op);
+        proj_context_log_debug(ctx, "Cannot export operation as a PROJ string");
         return nullptr;
     }
 
diff --git a/src/internal.cpp b/src/internal.cpp
index 3f3d191e..41744d16 100644
--- a/src/internal.cpp
+++ b/src/internal.cpp
@@ -416,6 +416,16 @@ void proj_log_debug (PJ *P, const char *fmt, ...) {
     va_end( args );
 }
 
+/*****************************************************************************/
+void proj_context_log_debug (PJ_CONTEXT *ctx, const char *fmt, ...) {
+/******************************************************************************
+   For reporting debugging information.
+******************************************************************************/
+    va_list args;
+    va_start( args, fmt );
+    pj_vlog (ctx, PJ_LOG_DEBUG_MAJOR , fmt, args);
+    va_end( args );
+}
 
 /*****************************************************************************/
 void proj_log_trace (PJ *P, const char *fmt, ...) {
diff --git a/src/proj_internal.h b/src/proj_internal.h
index d5154f78..e0999d88 100644
--- a/src/proj_internal.h
+++ b/src/proj_internal.h
@@ -111,6 +111,8 @@ void PROJ_DLL proj_log_error (PJ *P, const char *fmt, ...);
 void proj_log_debug (PJ *P, const char *fmt, ...);
 void proj_log_trace (PJ *P, const char *fmt, ...);
 
+void proj_context_log_debug (PJ_CONTEXT *ctx, const char *fmt, ...);
+
 int pj_ellipsoid (PJ *);
 void pj_inherit_ellipsoid_def (const PJ *src, PJ *dst);
 void pj_erase_ellipsoid_def (PJ *P);