add initial clang support

1 files changed, 23 insertions, 2 deletions

diff --git a/include/fortify-headers.h b/include/fortify-headers.h
index 5a3c6e5..42c8317 100644
--- a/include/fortify-headers.h
+++ b/include/fortify-headers.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015-2016 Dimitris Papastamos <sin@2f30.org>
+ * Copyright (C) 2022 q66 <q66@chimera-linux.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -16,10 +17,30 @@
 #ifndef _FORTIFY_HEADERS_H
 #define _FORTIFY_HEADERS_H
 
+#ifdef __clang__
+
+/* clang uses overloads; see https://github.com/llvm/llvm-project/issues/53516 */
+#define _FORTIFY_POSN(n) const __attribute__((__pass_object_size__(n)))
+/* we can't use extern inline with overloads without making them external */
+#define _FORTIFY_INLINE static __inline__ \
+        __attribute__((__always_inline__,__artificial__,__overloadable__))
+
+#else /* !__clang__ */
+
+#define _FORTIFY_POSN(n)
+#define _FORTIFY_INLINE extern __inline__ \
+        __attribute__((__always_inline__,__gnu_inline__,__artificial__))
+
+#endif /* __clang__ */
+
+#define _FORTIFY_POS0 _FORTIFY_POSN(0)
+#define _FORTIFY_POS1 _FORTIFY_POSN(1)
+#define _FORTIFY_POS2 _FORTIFY_POSN(2)
+
 #define _FORTIFY_STR(s) #s
 #define _FORTIFY_ORIG(p,fn) __typeof__(fn) __orig_##fn __asm__(_FORTIFY_STR(p) #fn)
-#define _FORTIFY_FN(fn) _FORTIFY_ORIG(__USER_LABEL_PREFIX__,fn); \
-        extern __inline__ __attribute__((__always_inline__,__gnu_inline__,__artificial__))
+#define _FORTIFY_FNB(fn) _FORTIFY_ORIG(__USER_LABEL_PREFIX__,fn)
+#define _FORTIFY_FN(fn) _FORTIFY_FNB(fn); _FORTIFY_INLINE
 
 
 /* Use __builtin_dynamic_object_size with _FORTIFY_SOURCE>2, if available.  */