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Subject: std::string across DLL boundaries
From: Ilia Mirkin <imirkin AT MIT DOT EDU>
To: cygwin AT cygwin DOT com
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Date: Wed, 04 Jan 2006 00:51:56 -0500
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Hi,

I've run into a problem passing a string ref to a dll:

testdll.C: (I've tried adding __declspec(dllimport/export) too)

void f(std::string& a) { a = "asdf"; }

test.C:

int main(void) { std::string a; f(a); std::cout << a << std::endl; }

If I compile it with static linking, the program works as expected. If f
is in a dll, then I can't get it to work -- different setups either go
into an infinite loop at a = "asdf", or dump core.

If, on the other hand, I do std::string a = "qwer", then it will work
fine -- it seems as though there may be a problem with the allocator in
libg++, though I may just be supplying the wrong flags to gcc.

Could someone either confirm that this is a problem, or, preferably,
provide instructions for getting this to compile "correctly"? (And if
this is a problem, are there known workarounds, is there a PR open
somewhere, etc)

Thanks,

Ilia

P.S. This works fine with MinGW, so it's not some huge windows dll
limitation.



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