[Bug libstdc++/60005] New: std::wcstod() doesn't work properly

[zizheng.tai at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60005

            Bug ID: 60005
           Summary: std::wcstod() doesn't work properly
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zizheng.tai at gmail dot com

According to cppreference, the second argument passed to std::wcstod, which is
a pointer to a pointer to wchar_t (i.e., of type wchar_t **), will 

1) be used to store the end of the converted part of the string if the argument
is not nullptr; or
2) not be used at all if the argument is nullptr.

However, when the following code is compiled and linked with mingw32-gcc4.8.0
on 32-bit Windows 7 with command line "g++ a.cpp -std=c++11 -Wall -Wextra", no
warning showed up but the program crashed when running.

// a.cpp
#include <cwchar>

int main()
{
    std::wcstod(L"5000", nullptr);

    return 0;
}

While the following code has no problem:

// acpp
#include <cwchar>

int main()
{
    wchar_t *p = nullptr;
    std::wcstod(L"5000", &p);

    return 0;
}