Re: [Boost-build] Anyone know what's up with bug #7212?

Subject: Re: [Boost-build] Anyone know what's up with bug #7212?
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2012-08-29 18:36:57

AMDG

On 08/29/2012 02:43 PM, Jurko Gospodnetić wrote:
>   Hi.
> 
>> To me, it smells compiler bug, but as this is a system where I cannot
>> "just update" the compiler, I am wondering if there are other
>> solutions.  I have a feeling that it is the loop/while/goto construct
>> that's complicating matters.
> 
>   We've confirmed this as a goto related compiler bug. :-)
> 
>   I'm attaching a patched function.c module based on revision [80313]
> that fixes the bug on the target system. I'll not commit it until we can
> find out more precisely which systems are affected by the bug.
> 
>   Steven, you have any more thoughts on why this would be causing problems?
> 

Not really.  I might be able to make a
guess if I had the assembler output for
the function and if you could isolate the
specific optimization flag that triggers it.
(One or more of -fthread-jumps -fcaller-saves
-fcrossjumping -fcse-follow-jumps  -fcse-skip-blocks
-fdelete-null-pointer-checks -fexpensive-optimizations
-fgcse -fgcse-lm -finline-small-functions
-findirect-inlining -fipa-sra -foptimize-sibling-calls
-fpeephole2 -fregmove -freorder-functions -frerun-cse-after-loop
-fsched-interblock -fsched-spec -fschedule-insns
-fschedule-insns2 -fstrict-overflow -ftree-switch-conversion
-ftree-pre -ftree-vrp)

If I had to make a guess I'd suspect -ftree-vrp
or possibly -ftree-pre.

In Christ,
Steven Watanabe