[Bug fortran/29621] lapack runs into infinite loop with -03

[sgk at troutmask dot apl dot washington dot edu]

------- Comment #15 from sgk at troutmask dot apl dot washington dot edu  2006-10-28 02:59 -------
Subject: Re:  lapack runs into infinite loop with -03

On Sat, Oct 28, 2006 at 02:07:00AM -0000, fkar at nemesis-project dot org
wrote:
> 
> > Are you building slamch.f and dlamch.f with -O3 or even -O1?
> > Don't.  These files try to determine machine values (e.g.,
> > epsilon).  Optimization can give some really strange answers.
> 
> Thank you!!!
> That totally solved the problem and now the program executes fine.
> 
> Is this a bug after all?
> 

No.  It is very old Fortran code that tries to 
be clever.  Unfortunately, aggressive optimization
will break the cleverness.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29621