Don't automatically add a #version to GL3 shaders on MacOS.

This messes up with custom shaders. MacOS is happy to use any specific
version above 330, depending on which features you are actually using in
the shader source.

Author: SiegeLordEx

src/opengl/ogl_shader.c

@@ -124,22 +124,7 @@ static bool glsl_attach_shader_source(ALLEGRO_SHADER *shader,
       if ((*handle) == 0) {
          return false;
       }
-#ifdef ALLEGRO_MACOSX
-      {
-         const char *version_string = glGetString(GL_SHADING_LANGUAGE_VERSION);
-         int version[2];
-         sscanf(version_string, "%d.%d", &version[0], &version[1]);
-         char version_line[] = "#version XXXXXXXXXX";
-         ASSERT(version[0] < 10 && version[1] < 100);
-         snprintf(version_line, sizeof(version_line), "#version %d%d\n", version[0], version[1]);
-
-         const char *sources[] = {version_line, source};
-
-         glShaderSource(*handle, 2, sources, NULL);
-      }
-#else
       glShaderSource(*handle, 1, &source, NULL);
-#endif
       glCompileShader(*handle);
       glGetShaderiv(*handle, GL_COMPILE_STATUS, &status);
       if (status == 0) {

src/shader_source.inc

@@ -38,6 +38,7 @@ static const char *default_glsl_vertex_source =
    "}\n";
 
 static const char *default_glsl_pixel_source =
+   "#version 330 core\n"
    "#ifdef GL_ES\n"
    "precision lowp float;\n"
    "#endif\n"
@@ -99,6 +100,7 @@ static const char *default_glsl_minimal_pixel_source =
    "}\n";
 
 static const char *default_glsl_vertex_source_gl3 =
+   "#version 330 core\n"
    "in vec4 " ALLEGRO_SHADER_VAR_POS ";\n"
    "in vec4 " ALLEGRO_SHADER_VAR_COLOR ";\n"
    "in vec2 " ALLEGRO_SHADER_VAR_TEXCOORD ";\n"
@@ -120,6 +122,7 @@ static const char *default_glsl_vertex_source_gl3 =
    "}\n";
 
 static const char *default_glsl_pixel_source_gl3 =
+   "#version 330 core\n"
    "#ifdef GL_ES\n"
    "precision lowp float;\n"
    "#endif\n"
@@ -163,6 +166,7 @@ static const char *default_glsl_pixel_source_gl3 =
    "}\n";
 
 static const char *default_glsl_minimal_pixel_source_gl3 =
+   "#version 330 core\n"
    "#ifdef GL_ES\n"
    "precision lowp float;\n"
    "#endif\n"