[libc] Only use __has_builtin on clang

The preprocessor reads the whole line even if the first condition of an and is false so this broke when compiling on older gcc versions which don't recognize `__has_builtin`

diff --git a/libc/src/string/memory_utils/memcpy_utils.h b/libc/src/string/memory_utils/memcpy_utils.h
index 7975d47..f6f283e 100644 (file)
--- a/libc/src/string/memory_utils/memcpy_utils.h
+++ b/libc/src/string/memory_utils/memcpy_utils.h
@@ -14,8 +14,10 @@
 
 // __builtin_memcpy_inline guarantees to never call external functions.
 // Unfortunately it is not widely available.
-#if defined(__clang__) && __has_builtin(__builtin_memcpy_inline)
+#ifdef __clang__
+#if __has_builtin(__builtin_memcpy_inline)
 #define USE_BUILTIN_MEMCPY_INLINE
+#endif
 #elif defined(__GNUC__)
 #define USE_BUILTIN_MEMCPY
 #endif