[Bug tree-optimization/14541] [tree-ssa] built-in math functions are not fully optimized at tree level

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=14541

--- Comment #24 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to ktkachov from comment #23)
> (In reply to Richard Biener from comment #22)
> > (In reply to ktkachov from comment #21)
> > > Created attachment 34215 [details]
> > > Link errors output for aarch64
> > > 
> > > > Which one exactly?  That is, what is the failing link output?
> > > 
> > > All of them AFAICS. I'm attaching the link failures log.
> > > 
> > > The test PASSes at -O2 -flto and -O2 -flto -flto-partition=none
> > > 
> > > but FAILs on all other torture options
> > 
> > With a cross to aarch64-linux and compiling with -O1+ -ffast-math the
> > result is as expected (optimized to empty functions).  How exactly
> > do you configure?  I used
> > 
> > /space/rguenther/src/svn/trunk2/configure --target=aarch64-suse-linux
> > --enable-languages=c,c++,fortran --enable-checking
> 
> Hmmm... My compiler is a bare-metal one: aarch64-none-elf (and I still see
> these failures).
> 
> With an aarch64-none-linux-gnu compiler the testcase works fine...

I have opened PR64313 for this regression.