[Bug libstdc++/93245] New: std::experimental::filesystem::path::generic_string() doesn't normalize

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93245

            Bug ID: 93245
           Summary: std::experimental::filesystem::path::generic_string()
                    doesn't normalize
           Product: gcc
           Version: 9.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redi at gcc dot gnu.org
  Target Milestone: ---

tmp$ cat gen.cc
#include <experimental/filesystem>

int main()
{
  if (std::experimental::filesystem::path("///").generic_string() != "/")
    throw 1;
}
tmp$ g++ gen.cc -lstdc++fs
tmp$ ./a.out
terminate called after throwing an instance of 'int'
Aborted (core dumped)

Adjacent directory separators should be normalized to a single one.

There is a test for this function, but it's a copy of some other test and
doesn't ever call generic_string()!