diff -up SDL2-2.0.9/include/SDL_opengl_glext.h.khrplatform SDL2-2.0.9/include/SDL_opengl_glext.h
--- SDL2-2.0.9/include/SDL_opengl_glext.h.khrplatform	2019-02-15 20:22:39.173773779 -0500
+++ SDL2-2.0.9/include/SDL_opengl_glext.h	2019-02-15 20:22:58.176399330 -0500
@@ -469,8 +469,9 @@ GLAPI void APIENTRY glBlendEquation (GLe
 typedef long GLsizeiptr;
 typedef long GLintptr;
 #else
-typedef ptrdiff_t GLsizeiptr;
-typedef ptrdiff_t GLintptr;
+#include <KHR/khrplatform.h>
+typedef khronos_intptr_t GLintptr;
+typedef khronos_ssize_t GLsizeiptr;
 #endif
 #define GL_BUFFER_SIZE                    0x8764
 #define GL_BUFFER_USAGE                   0x8765
