From: Carlo Marcelo Arenas Belón Date: Sun, 16 Jun 2019 18:40:03 +0000 (-0700) Subject: wrapper: avoid undefined behaviour in macOS X-Git-Tag: v2.23.0-rc0~77^2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=729a9b558b0408fdf60e39c96b04b33a333d8366;p=thirdparty%2Fgit.git wrapper: avoid undefined behaviour in macOS 0620b39b3b ("compat: add a mkstemps() compatibility function", 2009-05-31) included a function based on code from libiberty which would result in undefined behaviour in platforms where timeval's tv_usec is a 32-bit signed type as shown by: wrapper.c:505:31: runtime error: left shift of 594546 by 16 places cannot be represented in type '__darwin_suseconds_t' (aka 'int') interestingly the version of this code from gcc never had this bug and the code had a cast that would had prevented the issue (at least in 64-bit platforms) but was misapplied. change the cast to uint64_t so it also works in 32-bit platforms. Signed-off-by: Carlo Marcelo Arenas Belón Signed-off-by: Junio C Hamano --- diff --git a/wrapper.c b/wrapper.c index ea3cf64d4c..1e45ab7b92 100644 --- a/wrapper.c +++ b/wrapper.c @@ -502,7 +502,7 @@ int git_mkstemps_mode(char *pattern, int suffix_len, int mode) * Try TMP_MAX different filenames. */ gettimeofday(&tv, NULL); - value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid(); + value = ((uint64_t)tv.tv_usec << 16) ^ tv.tv_sec ^ getpid(); filename_template = &pattern[len - 6 - suffix_len]; for (count = 0; count < TMP_MAX; ++count) { uint64_t v = value;