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 O'Brien]

On Fri, Jan 14, 2005 at 05:28:29AM -0800, Kris Kennaway wrote:
> On Fri, Jan 14, 2005 at 08:24:33AM -0500, David Schultz wrote:
> > 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
...
> > > >   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.
> 
> OK :-(
> 
> Someone needs to revert amd64 back to using -O in the meantime, then.

I can't tell if you're talking about a need to move back to -O is for
/usr/ports or /usr/src?  If for /usr/ports, we should just change
ports/Mk/bsd.port.mk to s/-O2/-O/ on AMD64?  If we move back to -O in
/usr/src we'll never get all the issues found and ironed out.
 
-- 
-- David  (obrien at FreeBSD.org)