From 4d3eaeb4f505b0838c673ee28e7dba8687fc8272 Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Tue, 13 Jul 2021 12:21:27 +0100 Subject: [PATCH] libstdc++: Simplify basic_string_view::ends_with [PR 101361] The use of npos triggers a diagnostic as described in PR c++/101361. This change replaces the use of npos with the exact length, which is already known. We can further simplify it by inlining the effects of compare and substr, avoiding the redundant range checks in the latter. Signed-off-by: Jonathan Wakely libstdc++-v3/ChangeLog: PR c++/101361 * include/std/string_view (ends_with): Use traits_type::compare directly. --- libstdc++-v3/include/std/string_view | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/libstdc++-v3/include/std/string_view b/libstdc++-v3/include/std/string_view index cfdcf28..4ea72c6 100644 --- a/libstdc++-v3/include/std/string_view +++ b/libstdc++-v3/include/std/string_view @@ -361,8 +361,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION constexpr bool ends_with(basic_string_view __x) const noexcept { - return this->size() >= __x.size() - && this->compare(this->size() - __x.size(), npos, __x) == 0; + const auto __len = this->size(); + const auto __xlen = __x.size(); + return __len >= __xlen + && traits_type::compare(end() - __xlen, __x.data(), __xlen) == 0; } constexpr bool -- 2.7.4