Had to modify two header files to prevent errors and warnings when using libRocket in a MinGW compiled project. libRocket should now compile against mingw, and link in a mingw project. Huzzah!

Include/Rocket/Core/Debug.h

@@ -32,7 +32,11 @@
 
 // Define for breakpointing.
 #if defined (ROCKET_PLATFORM_WIN32)
-#define ROCKET_BREAK _asm { int 0x03 }
+	#if defined (__MINGW32__)
+		#define ROCKET_BREAK asm("int $0x03")
+	#else
+		#define ROCKET_BREAK _asm { int 0x03 }
+	#endif
 #elif defined (ROCKET_PLATFORM_LINUX)
 #define ROCKET_BREAK asm ("int $0x03" )
 #elif defined (ROCKET_PLATFORM_MACOSX)

Include/Rocket/Core/Platform.h

@@ -31,7 +31,9 @@
 #if defined __WIN32__ || defined _WIN32
 	#define ROCKET_PLATFORM_WIN32
 	#define ROCKET_PLATFORM_NAME "win32"
-    #pragma warning(disable:4355)
+	#if !defined(__MINGW32__)
+		#pragma warning(disable:4355)
+	#endif
 #elif defined __APPLE_CC__
 	#define ROCKET_PLATFORM_UNIX
 	#define ROCKET_PLATFORM_MACOSX
@@ -53,7 +55,7 @@
 #endif
 
 
-#if defined ROCKET_PLATFORM_WIN32
+#if defined(ROCKET_PLATFORM_WIN32) && !defined(__MINGW32__)
 	// alignment of a member was sensitive to packing
 	#pragma warning(disable : 4121)