Merge branch 'update-cmake-glew-test'

Fixes issue 6548

CMakeLists.txt

@@ -646,13 +646,13 @@ if(WIN32)
 else()
 	if(NOT ANDROID)
 		if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-			check_lib(GLEW GLEW GL/glew.h)
+			include(FindGLEW)
 		endif()
-		if(NOT GLEW_FOUND)
+		if(NOT GLEW_FOUND OR NOT GLEW_HAS_1_9_METHODS)
 			message("Using static GLEW from Externals")
 			add_subdirectory(Externals/GLew)
 			include_directories(Externals/GLew/include)
-		endif(NOT GLEW_FOUND)
+		endif()
 	endif()
 endif()
 

CMakeTests/FindGLEW.cmake

@@ -0,0 +1,32 @@
+include(FindPkgConfig OPTIONAL)
+
+# This is a hack to deal with Ubuntu's mess.
+# Ubuntu's version of glew is 1.8, but they have patched in most of glew 1.9.
+# So Ubuntu's version works for dolphin.
+macro(test_glew)
+	set(CMAKE_REQUIRED_INCLUDES ${GLEW_INCLUDE_DIRS})
+	set(CMAKE_REQUIRED_LIBRARIES GLEW)
+	check_cxx_source_runs("
+	#include <GL/glew.h>
+	int main()
+	{
+	#ifdef GLEW_ARB_shader_image_load_store
+	return 0;
+	#else
+	return 1;
+	#endif
+	}"
+	GLEW_HAS_1_9_METHODS)
+endmacro()
+
+if(PKG_CONFIG_FOUND AND NOT ${var}_FOUND)
+	pkg_search_module(GLEW REQUIRED glew>=1.8)
+endif()
+
+if(GLEW_FOUND)
+	test_glew()
+	if (GLEW_HAS_1_9_METHODS)
+		include_directories(${GLEW_INCLUDE_DIRS})
+		message("GLEW found")
+	endif()
+endif()