--- src/librdf.h
+++ src/librdf.h
@@ -74,7 +74,7 @@
 /* Use gcc 3.1+ feature to allow marking of deprecated API calls.
  * This gives a warning during compiling.
  */
-#if ( __GNUC__ == 3 && __GNUC_MINOR__ > 0 ) || __GNUC__ > 3
+#if (defined __GNUC__ && (( __GNUC__ == 3 && __GNUC_MINOR__ > 0 ) || __GNUC__ > 3)) || defined __clang__
 #define REDLAND_DEPRECATED __attribute__((deprecated))
 #define REDLAND_NORETURN __attribute__((__noreturn__))
 #else
@@ -83,7 +83,7 @@
 #endif
 
 
-#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4)
+#if (defined __GNUC__ && (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ > 4))) || defined __clang__
 #define REDLAND_PRINTF_FORMAT(string_index, first_to_check_index) \
   __attribute__((__format__(__printf__, string_index, first_to_check_index)))
 #else