Re: [Hakon.Bugge@scali.com] libc/1739: signal+siglongjmp destroys FP control word on x86

["H . J . Lu" <hjl at lucon dot org>]

On Mon, May 15, 2000 at 04:18:33PM +0200, Andreas Jaeger wrote:
> 
> Hi glibc folks,
> 
> We've received the appended bug report about signal/siglongjmp.
> 
> Hakon is right, we don't save anything at all about the FPU.
> 
> Looking at the description of setjmp in ISO C 1999, I found:
> 
>        The environment of a call to the setjmp macro consists of
>        information sufficient for a call to the longjmp function to
>        return execution to the correct block and invocation of that
>        block, were it called recursively.  It does not include the
>        state of the floating-point status flags, of open files, or of
>        any other component of the abstract machine.
> 
> Since siglongjmp is an extension of setjmp/longjmp only with respect
> to signal handling, it seems that I can close the bug report with the
> comment "You're right - but we're following the ISO C standard which
> explictly forbids this".
> 
> What do you think?
> 

For those who care, I have a kernel patch for the problem.



H.J.