Fix T46431: Init glew before glx-context crashes

Initialize glxew before glew,
so we can check whats supported before creating the context.

This also removes need for mxIgnoreNoVersion.

3 files changed, 5 insertions, 27 deletions

diff --git a/intern/ghost/intern/GHOST_ContextGLX.cpp b/intern/ghost/intern/GHOST_ContextGLX.cpp
index 4d45d493aa2..c431e7e2a01 100644
--- a/intern/ghost/intern/GHOST_ContextGLX.cpp
+++ b/intern/ghost/intern/GHOST_ContextGLX.cpp
@@ -40,9 +40,6 @@
 #include <cstdio>
 #include <cstring>
 
-/* this should eventually be enabled, but causes T46431 */
-// #define USE_CONTEXT_FLAGS
-
 #ifdef WITH_GLEW_MX
 GLXEWContext *glxewContext = NULL;
 #endif
@@ -156,19 +153,11 @@ GHOST_TSuccess GHOST_ContextGLX::initializeDrawingContext()
 	XIOErrorHandler old_handler_io = XSetIOErrorHandler(GHOST_X11_ApplicationIOErrorHandler);
 #endif
 
-#ifdef USE_CONTEXT_FLAGS
-	/* needed so 'GLXEW_ARB_create_context' is valid */
-	mxIgnoreNoVersion(1);
-	initContextGLXEW();
-	mxIgnoreNoVersion(0);
-#endif
+	/* important to initialize only glxew (_not_ glew),
+	 * since this breaks w/ Mesa's `swrast`, see: T46431 */
+	glxewInit();
 
-#ifdef USE_CONTEXT_FLAGS
-	if (GLXEW_ARB_create_context)
-#else
-	if (0)
-#endif
-	{
+	if (GLXEW_ARB_create_context) {
 		int profileBitCore   = m_contextProfileMask & GLX_CONTEXT_CORE_PROFILE_BIT_ARB;
 		int profileBitCompat = m_contextProfileMask & GLX_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB;
 
@@ -273,11 +262,9 @@ GHOST_TSuccess GHOST_ContextGLX::initializeDrawingContext()
 
 		glXMakeCurrent(m_display, m_window, m_context);
 
-#ifndef USE_CONTEXT_FLAGS
 		// Seems that this has to be called after MakeCurrent,
 		// which means we cannot use glX extensions until after we create a context
 		initContextGLXEW();
-#endif
 
 		initClearGL();
 		::glXSwapBuffers(m_display, m_window);
diff --git a/intern/glew-mx/glew-mx.h b/intern/glew-mx/glew-mx.h
index 92450d67812..ed17ea4a0e6 100644
--- a/intern/glew-mx/glew-mx.h
+++ b/intern/glew-mx/glew-mx.h
@@ -95,8 +95,6 @@ MXContext *mxGetCurrentContext (void);
 void       mxMakeCurrentContext(MXContext *ctx);
 void       mxDestroyContext    (MXContext *ctx);
 
-void       mxIgnoreNoVersion(int ignore);
-
 GLenum glew_chk(GLenum error, const char *file, int line, const char *text);
 
 #ifndef NDEBUG
diff --git a/intern/glew-mx/intern/glew-mx.c b/intern/glew-mx/intern/glew-mx.c
index 78920670f68..6fbb1a7a2e2 100644
--- a/intern/glew-mx/intern/glew-mx.c
+++ b/intern/glew-mx/intern/glew-mx.c
@@ -34,8 +34,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-static int ignore_version = 0;
-
 #define CASE_CODE_RETURN_STR(code) case code: return #code;
 
 static const char *get_glew_error_enum_string(GLenum error)
@@ -63,7 +61,7 @@ GLenum glew_chk(GLenum error, const char *file, int line, const char *text)
 		const char *code = get_glew_error_enum_string(error);
 		const char *msg  = (const char *)glewGetErrorString(error);
 
-		if (error == GLEW_ERROR_NO_GL_VERSION && ignore_version)
+		if (error == GLEW_ERROR_NO_GL_VERSION)
 			return GLEW_OK;
 
 #ifndef NDEBUG
@@ -144,8 +142,3 @@ void mxDestroyContext(MXContext *ctx)
 	(void)ctx;
 #endif
 }
-
-void mxIgnoreNoVersion(int ignore)
-{
-	ignore_version = ignore;
-}