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Date: Wed, 12 Jul 2017 13:12:00 -0000
From: Takashi Yano <takashi.yano@nifty.ne.jp>
To: cygwin@cygwin.com
Subject: 64 bit g++ 5.4.0 bug
Message-Id: <20170712221212.535f6c54545b1296142bab7c@nifty.ne.jp>
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Hello.

I have encountered a weird behaviour of g++ compiler.

If the following code is compiled with -ansi -O flags,
the resulting executable causes core dump.

This is caused only in 64 bit environment. In 32 bit
environment, it works as expected.

$ cat str.cc
#include <string>
int main()
{
        std::string s;
        s = "ABC";
        return 0;
}
$ g++ -ansi -O str.cc -o str
$ ./str
Abort (core dumped)
$

Is this known problem?

My environment is as follows.

uname -a
CYGWIN_NT-10.0 Express5800-S70 2.8.1(0.312/5/3) 2017-07-03 14:11 x86_64 Cygwin

g++ --version
g++ (GCC) 5.4.0
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Thank you in advance.

-- 
Takashi Yano <takashi.yano@nifty.ne.jp>

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