diff --git a/src/gl-fun.h b/src/gl-fun.h
index bae8dc3..42cd4d7 100644
--- a/src/gl-fun.h
+++ b/src/gl-fun.h
@@ -69,7 +69,7 @@ typedef void (APIENTRYP PFNGLBUFFERSUBDATAPROC) (GLenum target, GLintptr offset,
 /* Shader */
 typedef GLuint (APIENTRYP PFNGLCREATESHADERPROC) (GLenum type);
 typedef void (APIENTRYP PFNGLDELETESHADERPROC) (GLuint shader);
-typedef void (APIENTRYP PFNGLSHADERSOURCEPROC) (GLuint shader, GLsizei count, const GLchar** strings, const GLint* lengths);
+typedef void (APIENTRYP PFNGLSHADERSOURCEPROC) (GLuint shader, GLsizei count, const GLchar* const* strings, const GLint* lengths);
 typedef void (APIENTRYP PFNGLCOMPILESHADERPROC) (GLuint shader);
 typedef void (APIENTRYP PFNGLATTACHSHADERPROC) (GLuint program, GLuint shader);
 typedef void (APIENTRYP PFNGLGETSHADERIVPROC) (GLuint shader, GLenum pname, GLint* param);