From 7c9841b8428edfbc369eccf54788b668d4b27328 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Sat, 23 Jan 2021 11:35:44 -0800 Subject: [PATCH] Update from Gnulib by running admin/merge-gnulib --- lib/cdefs.h | 6 ++++-- lib/explicit_bzero.c | 16 +++++++++++++--- 2 files changed, 17 insertions(+), 5 deletions(-) diff --git a/lib/cdefs.h b/lib/cdefs.h index de74f4211cf..17a0919cd83 100644 --- a/lib/cdefs.h +++ b/lib/cdefs.h @@ -320,14 +320,16 @@ #endif /* The nonnull function attribute marks pointer parameters that - must not be NULL. Do not define __nonnull if it is already defined, - for portability when this file is used in Gnulib. */ + must not be NULL. */ #ifndef __nonnull # if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__) # define __nonnull(params) __attribute__ ((__nonnull__ params)) # else # define __nonnull(params) # endif +#elif !defined __GLIBC__ +# undef __nonnull +# define __nonnull(params) _GL_ATTRIBUTE_NONNULL (params) #endif /* If fortification mode, we warn about unused results of certain diff --git a/lib/explicit_bzero.c b/lib/explicit_bzero.c index feea4446c06..f50ed0875d7 100644 --- a/lib/explicit_bzero.c +++ b/lib/explicit_bzero.c @@ -54,11 +54,21 @@ explicit_bzero (void *s, size_t len) 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"); -# endif +#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 . */ + __asm__ volatile ("" : : "g"(s) : "memory"); +#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 } -- 2.39.5