diff --git a/utils/fake_libc_include/_fake_typedefs.h b/utils/fake_libc_include/_fake_typedefs.h
index b15e50ee..f5db1de0 100644
--- a/utils/fake_libc_include/_fake_typedefs.h
+++ b/utils/fake_libc_include/_fake_typedefs.h
@@ -153,6 +153,12 @@ typedef int uintmax_t;
 /* C99 stdbool.h bool type. _Bool is built-in in C99 */
 typedef _Bool bool;
 
+/* GNU Extension for 64-bit targets */
+#ifdef __SIZEOF_INT128__
+typedef int __int128_t;
+typedef int __uint128_t;
+#endif /* __SIZEOF_INT128__ */
+
 /* Mir typedefs */
 typedef void* MirEGLNativeWindowType;
 typedef void* MirEGLNativeDisplayType;