How to report bugs only seen with -flto?

[Markus Trippelsdorf]

On 2012.06.28 at 07:40 +0200, Georg-Johann Lay wrote:
> Ian Lance Taylor schrieb:
> > Georg-Johann Lay <avr@gjlay.de> writes:
> > 
> >> The reporting instructions from
> >> http://gcc.gnu.org/bugs/#need
> >> don't outline how to report bugs that only occur with -flto
> >>
> >> Presumably, the bug to report is not a genuine LTO issue,
> >> but only because the compiler sees code/bunch of input
> >> files it does not see without -flto.
> >>
> >> How should such problems that involve possibly many files
> >> be reported?
> > 
> > The key is always to provide all the information required for somebody
> > else to recreate the problem.
> > 
> > Ian
> 
> Yes, of course.
> 
> The question is how to supply that information if dozens of sources are
> involved. Making dozens of attachments/comments?

Normally you can reduce your LTO test case to very few files. Just
follow the suggestions in:
http://gcc.gnu.org/wiki/A_guide_to_testcase_reduction#Reducing_LTO_bugs

-- 
Markus