[Bug bootstrap/92927] New: Bootstrap failed with CXXFLAGS="-O0"

[wwwhhhyyy333 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92927

            Bug ID: 92927
           Summary: Bootstrap failed with CXXFLAGS="-O0"
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
          Assignee: unassigned at gcc dot gnu.org
          Reporter: wwwhhhyyy333 at gmail dot com
  Target Milestone: ---

configure GCC with: --enable-languages=c,c++,fortran --enable-bootstrap
CXXFLAGS="-O0"

At stage3, it throws error:

/usr/bin/ld:
/home/hongyuw1/gcc/build_libstdcpp_regression/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs/libstdc++.a(string-inst.o):
in function `std::__cxx11::basic_string<char, std::char_traits<char>,
std::allocator<char> >::operator=(std::__cxx11::basic_string<char,
std::char_traits<char>, std::allocator<char> >&&)':
/home/hongyuw1/gcc/build_libstdcpp_regression/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/basic_string.h:716:
undefined reference to `void std::__alloc_on_move<std::allocator<char>
>(std::allocator<char>&, std::allocator<char>&)'
/usr/bin/ld:
/home/hongyuw1/gcc/build_libstdcpp_regression/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs/libstdc++.a(string-inst.o):
in function `std::__cxx11::basic_string<char, std::char_traits<char>,
std::allocator<char> >::assign(std::__cxx11::basic_string<char,
std::char_traits<char>, std::allocator<char> > const&)':
/home/hongyuw1/gcc/build_libstdcpp_regression/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/basic_string.h:1363:
undefined reference to `void std::__alloc_on_copy<std::allocator<char>
>(std::allocator<char>&, std::allocator<char> const&)'
/usr/bin/ld:
/home/hongyuw1/gcc/build_libstdcpp_regression/prev-x86_64-pc-linux-gnu/libstdc++-v3/src/.libs/libstdc++.a(string-inst.o):
in function `__gnu_cxx::__alloc_traits<std::allocator<char>,
char>::_S_on_swap(std::allocator<char>&, std::allocator<char>&)':
/home/hongyuw1/gcc/build_libstdcpp_regression/x86_64-pc-linux-gnu/libstdc++-v3/include/ext/alloc_traits.h:101:
undefined reference to `void std::__alloc_on_swap<std::allocator<char>
>(std::allocator<char>&, std::allocator<char>&)'
collect2: error: ld returned 1 exit status
make[3]: *** [Makefile:2943: gcov] Error 1

It seems to happen after r277588.