https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96798
--- Comment #9 from Iain Sandoe <iains at gcc dot gnu.org> --- (In reply to Iain Sandoe from comment #8) > (In reply to Iain Sandoe from comment #7) > > (In reply to David Malcolm from comment #6) > > > Thanks! The "memset" call has become a call to "__builtin___memset_chk" > > > (perhaps due to _FORTIFY_SOURCE, or something similar in Darwin's libc?), > > > > (transitive include of strings.h, for macOS >= 10.5) > > usr/include/_types.h:# define _FORTIFY_SOURCE 2 /* on by default */ > > > > usr/include/strings.h: > > > > #if defined (__GNUC__) && _FORTIFY_SOURCE > 0 && !defined (__cplusplus) > > /* Security checking functions. */ > > #include <secure/_strings.h> > > #endif > > > > > > secure/_strings.h: > > > > #if _USE_FORTIFY_LEVEL > 0 > > > > .... > > > > #if __has_builtin(__builtin___memset_chk) || defined(__GNUC__) > > #undef bzero > > /* void bzero(void *s, size_t n) */ > > #define bzero(dest, ...) \ > > __builtin___memset_chk (dest, 0, __VA_ARGS__, __darwin_obsz0 > > (dest)) > > #endif > > > > Oops hit send too soon. > > string.h is a transitive include of strings.h and has: > #if defined (__GNUC__) && _FORTIFY_SOURCE > 0 && !defined (__cplusplus) > /* Security checking functions. */ > #include <secure/_string.h> > #endif > > _strings.h: ^^ typo -- secure/_string.h: > > #if __IPHONE_OS_VERSION_MIN_REQUIRED >= 70000 || > __MAC_OS_X_VERSION_MIN_REQUIRED >= 1090 || \ > defined(__DRIVERKIT_VERSION_MIN_REQUIRED) > #if __has_builtin(__builtin___memccpy_chk) && __HAS_FIXED_CHK_PROTOTYPES > #undef memccpy > /* void *memccpy(void *dst, const void *src, int c, size_t n) */ > #define memccpy(dest, ...) \ > __builtin___memccpy_chk (dest, __VA_ARGS__, __darwin_obsz0 > (dest)) > #endif > #endif > > So.. essentially, the checked builtins are going to be used everywhere by > default on modern Darwin (and some are going to be used even on venerable > Darwin).
