Long double text misprinted with iostreams on MinGW

Question

Consider the code

#include <iostream>

int main() {
  std::cout << 4.2L;
}

Compile it on MinGW and run the results in the next release:

> g++ test.cc
> a.exe
-7.89773e-278

Is this a bug in MinGW and is there a fix or workaround?

Update:

A similar problem is printfdescribed in this question :

#include <cstdio>

int main() {
  std::printf("%Lg", 4.2L); // prints -7.89773e-278
}

However, the problem with printfcan be fixed by determining __USE_MINGW_ANSI_STDIOuntil it can be, so I think it deserves a separate question.

Answer 1

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