[Bug libstdc++/81092] New: Missing symbols for new std::wstring constructors

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81092

            Bug ID: 81092
           Summary: Missing symbols for new std::wstring constructors
           Product: gcc
           Version: 7.1.0
            Status: UNCONFIRMED
          Keywords: link-failure
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redi at gcc dot gnu.org
  Target Milestone: ---

This fails to link for targets where size_t != unsigned long (e.g. ia32)

#define _GLIBCXX_USE_CXX11_ABI 0
#include <string>

using std::wstring;

struct S : wstring {
  S(wstring s) : wstring(s, 1, s.get_allocator()) { }
};

int main()
{
  wstring s;
  wstring s2(s, 1, s.get_allocator());
  S s3(s);
}

$ g++-7 -g  s.cc -Wl,--no-demangle -m32
/tmp/ccPTDy8v.o: In function `main':
/tmp/s.cc:13: undefined reference to
`_ZNSbIwSt11char_traitsIwESaIwEEC1ERKS2_jRKS1_'
/tmp/ccPTDy8v.o: In function `_ZN1SC2ESbIwSt11char_traitsIwESaIwEE':
/tmp/s.cc:7: undefined reference to
`_ZNSbIwSt11char_traitsIwESaIwEEC2ERKS2_jRKS1_'
collect2: error: ld returned 1 exit status