darwin: Suppress type conversion warnings for GLhandleARB

This patch and its description are inspired from Jose Fonseca
explanations and suggestions.

With this patch the following logic applies and only if __APPLE__:

When building mesa, GLhandleARB is defined as unsigned long and
at some point casted to GLuint in gl fuction implementations.
These exact points are where these errors and warnings appear.

When building an application GLhandleARB is defined as void*.
Later when calling a gl function, for example glBindAttribLocationARB,
it will be dispatched to _mesa_BindAttribLocation. So internally
void* will be treated as unsigned long which has the same size.
So the same truncation happens when casting it to GLuint.

Same when GLhandleARB appears as return value.
For mesa it will be GLuint -> unsigned long.
For an application it will be GLuint -> unsigned long -> void*.
Note that the value will be preserved when casting back to GLuint.

When GLhandleARB appears as a pointer there are also separate
entry-points, i.e. _mesa_FuncNameARB. So the same logic can
be applied.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66346
Signed-off-by: Julien Isorce <julien.isorce@gmail.com>
Reviewed-by: Jose Fonseca <jfonseca@vmware.com>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>

diff --git a/configure.ac b/configure.ac
index d240c06057360542964ab72842d9e30eba942dc0..d819beffa50a472d6dcce747cb474d2dc9c3d540 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -1354,7 +1354,7 @@ if test "x$enable_dri" = xyes; then
         fi
         ;;
     darwin*)
-        DEFINES="$DEFINES -DGLX_ALIAS_UNSUPPORTED"
+        DEFINES="$DEFINES -DGLX_ALIAS_UNSUPPORTED -DBUILDING_MESA"
         if test "x$with_dri_drivers" = "xyes"; then
             with_dri_drivers="swrast"
         fi

diff --git a/include/GL/glext.h b/include/GL/glext.h
index a3873a613f9e5cefa41df79729c8f81111127535..e5f1d891ec599d188cc26472a565c2d2cde8c944 100644 (file)
--- a/include/GL/glext.h
+++ b/include/GL/glext.h
@@ -3879,7 +3879,12 @@ GLAPI void APIENTRY glMinSampleShadingARB (GLfloat value);
 #ifndef GL_ARB_shader_objects
 #define GL_ARB_shader_objects 1
 #ifdef __APPLE__
+#ifdef BUILDING_MESA
+/* Avoid uint <-> void* warnings */
+typedef unsigned long GLhandleARB;
+#else
 typedef void *GLhandleARB;
+#endif
 #else
 typedef unsigned int GLhandleARB;
 #endif