2021-01-23 Bastien Roucariès <rouca@debian.org>
+ explicit_bzero: Add fallback for other compilers.
+ * lib/explicit_bzero.c (explicit_bzero): For other compilers, invoke
+ memset through a volatile function pointer.
+
explicit_bzero: Add support for clang.
* lib/explicit_bzero.c (explicit_bzero): Add a compiler barrier for
clang.
explicit_memset (s, '\0', len);
#elif HAVE_MEMSET_S
(void) memset_s (s, len, '\0', len);
-#else
+#elif defined __GNUC__ && !defined __clang__
memset (s, '\0', len);
-# if defined __GNUC__ && !defined __clang__
/* Compiler barrier. */
asm volatile ("" ::: "memory");
-# elif defined __clang__
+#elif defined __clang__
+ memset (s, '\0', len);
/* Compiler barrier. */
/* With asm ("" ::: "memory") LLVM analyzes uses of 's' and finds that the
whole thing is dead and eliminates it. Use 'g' to work around this
problem. See <https://bugs.llvm.org/show_bug.cgi?id=15495#c11>. */
__asm__ volatile ("" : : "g"(s) : "memory");
-# endif
+#else
+ /* Invoke memset through a volatile function pointer. This defeats compiler
+ optimizations. */
+ void * (* const volatile volatile_memset) (void *, int, size_t) = memset;
+ (void) volatile_memset (s, '\0', len);
#endif
}