diff --git a/hw/xwin/glx/glshim.c b/hw/xwin/glx/glshim.c
index 7109196c0..df5a932ff 100644
--- a/hw/xwin/glx/glshim.c
+++ b/hw/xwin/glx/glshim.c
@@ -36,6 +36,7 @@
 #endif
 
 #define GL_GLEXT_LEGACY
+#define GL_GLEXT_PROTOTYPES
 #include <GL/gl.h>
 #undef GL_ARB_imaging
 #undef GL_VERSION_1_3
@@ -46,6 +47,8 @@
 #include "glwindows.h"
 #include <glx/glxserver.h>
 
+extern void *glXGetProcAddressARB(const char *);
+
 static HMODULE hMod = NULL;
 
 /*