| From 50dd920299f8f905f47475bf77c299d9a84512b8 Mon Sep 17 00:00:00 2001 |
| From: Jason Merrill <jason@redhat.com> |
| Date: Thu, 18 Aug 2022 23:53:16 -0400 |
| Subject: [PATCH] libstdc++: avoid bogus -Wrestrict [PR105651] |
| To: gcc-patches@gcc.gnu.org |
| |
| PR tree-optimization/105651 |
| |
| libstdc++-v3/ChangeLog: |
| |
| * include/bits/basic_string.tcc (_M_replace): Add an assert |
| to avoid -Wrestrict false positive. |
| --- |
| libstdc++-v3/include/bits/basic_string.tcc | 3 +++ |
| 1 file changed, 3 insertions(+) |
| |
| diff --git a/libstdc++-v3/include/bits/basic_string.tcc b/libstdc++-v3/include/bits/basic_string.tcc |
| index 4563c61429a..0d5c4d6191e 100644 |
| --- a/libstdc++-v3/include/bits/basic_string.tcc |
| +++ b/libstdc++-v3/include/bits/basic_string.tcc |
| @@ -529,6 +529,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION |
| { |
| const size_type __nleft = (__p + __len1) - __s; |
| this->_S_move(__p, __s, __nleft); |
| + // Tell the middle-end that the copy can't overlap |
| + // (PR105651). |
| + if (__len2 < __nleft) __builtin_unreachable (); |
| this->_S_copy(__p + __nleft, __p + __len2, |
| __len2 - __nleft); |
| } |
| -- |
| 2.31.1 |
