From 6759eddee476abdfb5e847a7de3765309f4f1e2d Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Fri, 29 May 2015 14:28:54 +0100 Subject: [PATCH] re PR libstdc++/66327 (-fsanitize=nonnull-attribute errors in stl_algobase.h) PR libstdc++/66327 * include/bits/stl_algobase.h (__equal::equal): Do not call memcmp with null pointers. (__lexicographical_compare::__lc): Do not call memcmp for empty ranges. From-SVN: r223865 --- libstdc++-v3/ChangeLog | 8 ++++++++ libstdc++-v3/include/bits/stl_algobase.h | 15 ++++++++++++--- 2 files changed, 20 insertions(+), 3 deletions(-) diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 286197c..94c7963 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,11 @@ +2015-05-29 Jonathan Wakely + + PR libstdc++/66327 + * include/bits/stl_algobase.h (__equal::equal): Do not call + memcmp with null pointers. + (__lexicographical_compare::__lc): Do not call memcmp for empty + ranges. + 2015-05-28 Jonathan Wakely PR libstdc++/65352 diff --git a/libstdc++-v3/include/bits/stl_algobase.h b/libstdc++-v3/include/bits/stl_algobase.h index 409ef36..db065e2 100644 --- a/libstdc++-v3/include/bits/stl_algobase.h +++ b/libstdc++-v3/include/bits/stl_algobase.h @@ -812,6 +812,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION static bool equal(const _Tp* __first1, const _Tp* __last1, const _Tp* __first2) { + if (__first1 == 0 || __first2 == 0) + return __first1 == __last1; + return !__builtin_memcmp(__first1, __first2, sizeof(_Tp) * (__last1 - __first1)); } @@ -917,9 +920,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { const size_t __len1 = __last1 - __first1; const size_t __len2 = __last2 - __first2; - const int __result = __builtin_memcmp(__first1, __first2, - std::min(__len1, __len2)); - return __result != 0 ? __result < 0 : __len1 < __len2; + if (__len1 && __len2) + { + if (int __result = __builtin_memcmp(__first1, __first2, + std::min(__len1, __len2))) + { + return __result < 0; + } + } + return __len1 < __len2; } }; -- 2.7.4