[Bug testsuite/111883] New: Wstringop-overflow-6.C FAILs with -std=c++26

[mpolacek at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111883

            Bug ID: 111883
           Summary: Wstringop-overflow-6.C FAILs with -std=c++26
           Product: gcc
           Version: 13.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: testsuite
          Assignee: unassigned at gcc dot gnu.org
          Reporter: mpolacek at gcc dot gnu.org
  Target Milestone: ---

FAIL: g++.dg/warn/Wstringop-overflow-6.C  -std=gnu++26 (test for excess errors)

the excess warning is:

$ xg++ -c Wstringop-overflow-6.C  -std=gnu++26 -O2 -Wall -Wsystem-headers 
In file included from
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/basic_string.h:51,
                 from
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/string:54,
                 from
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/locale_classes.h:40,
                 from
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/ios_base.h:41,
                 from
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/ios:44,
                 from
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/ostream:40,
                 from
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/iostream:41,
                 from Wstringop-overflow-6.C:6:
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/charconv: In
function ‘std::from_chars_result std::from_chars(const char*, const char*,
_Float16&, chars_format)’:
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/charconv:687:17:
warning: converting to ‘_Float16’ from ‘float’ with greater conversion rank
  687 |       __value = __val;
      |                 ^~~~~
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/charconv: In
function ‘std::from_chars_result std::from_chars(const char*, const char*,
__gnu_cxx::__bfloat16_t&, chars_format)’:
/home/mpolacek/x/trunk/x86_64-pc-linux-gnu/libstdc++-v3/include/charconv:763:17:
warning: converting to ‘__gnu_cxx::__bfloat16_t’ {aka ‘__bf16’} from ‘float’
with greater conversion rank
  763 |       __value = __val;
      |                 ^~~~~