cvs commit: src/lib/msun/alpha fenv.h src/lib/msun/amd64 fenv.h src/lib/msun/arm fenv.h src/lib/msun/i387 fenv.h src/lib/msun/ia64 fenv.h src/lib/msun/powerpc fenv.h src/lib/msun/sparc64 fenv.h

[David Schultz]

On Fri, Jan 14, 2005, Kris Kennaway wrote:
> On Fri, Jan 14, 2005 at 07:09:23AM +0000, David Schultz wrote:
> > das         2005-01-14 07:09:23 UTC
> > 
> >   FreeBSD src repository
> > 
> >   Modified files:
> >     lib/msun/alpha       fenv.h 
> >     lib/msun/amd64       fenv.h 
> >     lib/msun/arm         fenv.h 
> >     lib/msun/i387        fenv.h 
> >     lib/msun/ia64        fenv.h 
> >     lib/msun/powerpc     fenv.h 
> >     lib/msun/sparc64     fenv.h 
> >   Log:
> >   Mark all inline asms that read the floating-point control or status
> >   registers as volatile.  Instructions that *wrote* to FP state were
> >   already marked volatile, but apparently gcc has license to move
> >   non-volatile asms past volatile asms.  This broke amd64's feupdateenv
> >   at -O2 due to a WAR conflict between fnstsw and fldenv there.
> 
> Do you think this is likely to the cause of the build failures
> reported with a number of ports when world is compiled with -O2
> (i.e. does the feupdateenv failure cascade to other commonly-used
> parts of the code)?

No, this would lead to a runtime failure, and I would be surprised
if very many ports use fenv.h anyway.