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Mail Archives: cygwin/2012/02/08/01:38:11

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Date: Wed, 08 Feb 2012 07:37:37 +0100
From: Christian Franke <Christian DOT Franke AT t-online DOT de>
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To: cygwin AT cygwin DOT com
Subject: Re: Bug in sys/wait.h with C++
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Christopher Faylor wrote:
> On Tue, Feb 07, 2012 at 08:39:46PM -0600, Yaakov (Cygwin/X) wrote:
>> Just came across an issue with<sys/wait.h>  in C++.  STC:
>>
>> $ cat test.c
>> #include<stddef.h>
>> #include<sys/wait.h>
>> int main(void) { wait(NULL); return 0; }
>>
>> $ gcc -Wall test.c
>>
>> $ gcc -x c++ -Wall test.c
>> test.c: In function ???int main()???:
>> test.c:2:27: error: call of overloaded ???wait(NULL)??? is ambiguous
>> /usr/include/sys/wait.h:37:7: note: candidates are: pid_t wait(int*)
>> /usr/include/sys/wait.h:82:14: note:                 pid_t wait(wait*)
>>
>> This code compiles cleanly on Linux.
> I guess we have to incorporate Linux's head-standing in
> /usr/include/sys/wait.h to allow both the use of union wait * and int as
> arguments to wait().

Yes. Unfortunately the typesafe approach from
http://cygwin.com/ml/cygwin-patches/2011-q4/msg00003.html
does not work with NULL (0 in C++), sorry.

Workaround: wait((int *)0) or wait((union wait *)0);


> Anyone want to send a patch to cygwin-patches?

I'll do soon.

Christian


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