Re: Bug in sys/wait.h with C++

[Christian Franke <Christian dot Franke at t-online dot de>]

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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