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To: cygwin AT cygwin DOT com
From: Steven Brown <swbrown AT ucsd DOT edu>
Subject:  Reproducible, simple bug; g++ toolchain / std::string bug?
Date:  Fri, 07 Apr 2006 17:34:09 -0700
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I've run into what appears to be a bug in the g++ toolchain or the STL's 
std::string using the latest Cygwin dist (up to date as of right now). 
Minimal test case attached.

If my shared library does a callback to a function returning 
std::string, and only if the std::string is empty, I get an abort when 
that std::string is destroyed.

The attached files will show this bug - run make and the xxx-cygwin.exe 
that's produced and it will abort.  The same will happen if you use 
libtool to build it the right way - the autoconf/ dir in the bug's 
repository[1] can be used for that if you want to see it (copy it into 
the main dir, ./autogen.sh && make).

Any ideas as to where the problem lies or how to further identify it?


[1] https://svn.variadic.org/public/trunk/weirdbug/

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all: xxx-cygwin

xxx-cygwin: testit.cc xxx.cc
	g++ -g -O2 -shared testit.cc -o testit-cygwin.dll && g++ -g -O2 xxx.cc testit-cygwin.dll -o xxx-cygwin.exe

clean:
	rm -f testit-cygwin.dll xxx-cygwin.exe

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#include "testit.hpp"
#include <iostream>
using namespace std;

void testit(std::string (*contentGet)()) {
  contentGet();
}

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#include <string>

void testit(std::string (*contentGet)());

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#include "testit.hpp"
#include <iostream>
using namespace std;

std::string contentGet() {
  return string(""); // Anything other than empty string works.
}

int main() {
  testit(&contentGet);
  return 0;
}


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