diff --git a/src/gui/sdlmain.cpp b/src/gui/sdlmain.cpp
index e4973bbb..b2551fdc 100644
--- a/src/gui/sdlmain.cpp
+++ b/src/gui/sdlmain.cpp
@@ -110,7 +110,8 @@ typedef void (APIENTRYP PFNGLGETSHADERIVPROC) (GLuint shader, GLenum pname, GLin
 typedef void (APIENTRYP PFNGLGETSHADERINFOLOGPROC) (GLuint shader, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
 typedef GLint (APIENTRYP PFNGLGETUNIFORMLOCATIONPROC) (GLuint program, const GLchar *name);
 typedef void (APIENTRYP PFNGLLINKPROGRAMPROC) (GLuint program);
-typedef void (APIENTRYP PFNGLSHADERSOURCEPROC) (GLuint shader, GLsizei count, const GLchar **string, const GLint *length);
+//Change to NP, as Khronos changes include guard :(
+typedef void (APIENTRYP PFNGLSHADERSOURCEPROC_NP) (GLuint shader, GLsizei count, const GLchar **string, const GLint *length);
 typedef void (APIENTRYP PFNGLUNIFORM2FPROC) (GLint location, GLfloat v0, GLfloat v1);
 typedef void (APIENTRYP PFNGLUNIFORM1IPROC) (GLint location, GLint v0);
 typedef void (APIENTRYP PFNGLUSEPROGRAMPROC) (GLuint program);
@@ -136,7 +137,7 @@ PFNGLGETSHADERIVPROC glGetShaderiv = NULL;
 PFNGLGETSHADERINFOLOGPROC glGetShaderInfoLog = NULL;
 PFNGLGETUNIFORMLOCATIONPROC glGetUniformLocation = NULL;
 PFNGLLINKPROGRAMPROC glLinkProgram = NULL;
-PFNGLSHADERSOURCEPROC glShaderSource = NULL;
+PFNGLSHADERSOURCEPROC_NP glShaderSource = NULL;
 PFNGLUNIFORM2FPROC glUniform2f = NULL;
 PFNGLUNIFORM1IPROC glUniform1i = NULL;
 PFNGLUSEPROGRAMPROC glUseProgram = NULL;
@@ -1757,7 +1758,7 @@ static void GUI_StartUp(Section * sec) {
 			glGetShaderInfoLog = (PFNGLGETSHADERINFOLOGPROC)SDL_GL_GetProcAddress("glGetShaderInfoLog");
 			glGetUniformLocation = (PFNGLGETUNIFORMLOCATIONPROC)SDL_GL_GetProcAddress("glGetUniformLocation");
 			glLinkProgram = (PFNGLLINKPROGRAMPROC)SDL_GL_GetProcAddress("glLinkProgram");
-			glShaderSource = (PFNGLSHADERSOURCEPROC)SDL_GL_GetProcAddress("glShaderSource");
+			glShaderSource = (PFNGLSHADERSOURCEPROC_NP)SDL_GL_GetProcAddress("glShaderSource");
 			glUniform2f = (PFNGLUNIFORM2FPROC)SDL_GL_GetProcAddress("glUniform2f");
 			glUniform1i = (PFNGLUNIFORM1IPROC)SDL_GL_GetProcAddress("glUniform1i");
 			glUseProgram = (PFNGLUSEPROGRAMPROC)SDL_GL_GetProcAddress("glUseProgram");