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 <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	PR c++/101361
	* include/std/string_view (ends_with): Use traits_type::compare
	directly.
This commit is contained in:
Jonathan Wakely 2021-07-13 12:21:27 +01:00
parent f75560398a
commit 4d3eaeb4f5

View file

@ -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