Allow merging of units with profile feedback run different amount of times

[H.J. Lu]

On Sun, Dec 5, 2010 at 3:38 AM, Jan Hubicka <hubicka@ucw.cz> wrote:
>> I still got
>>
>> [hjl@gnu-18 gcc]$
>> /export/build/gnu/gcc-lto/build-x86_64-linux/./prev-gcc/xgcc
>> -B/export/build/gnu/gcc-lto/build-x86_64-linux/./prev-gcc/
>> -B/usr/gcc-4.6.0/x86_64-unknown-linux-gnu/bin/
>> -B/usr/gcc-4.6.0/x86_64-unknown-linux-gnu/bin/
>> -B/usr/gcc-4.6.0/x86_64-unknown-linux-gnu/lib/ -isystem
>> /usr/gcc-4.6.0/x86_64-unknown-linux-gnu/include -isystem
>> /usr/gcc-4.6.0/x86_64-unknown-linux-gnu/sys-include      -g -O2
>> -flto=jobserver -fuse-linker-plugin -frandom-seed=1 -fprofile-use
>> -DIN_GCC   -W -Wall -Wwrite-strings -Wcast-qual -Wstrict-prototypes
>> -Wmissing-prototypes -Wmissing-format-attribute -pedantic
>> -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror
>> -Wold-style-definition -Wc++-compat -fno-common  -DHAVE_CONFIG_H
>> -DGENERATOR_FILE -static-libstdc++ -static-libgcc  -o
>> build/genchecksum build/genchecksum.o .././libiberty/libiberty.a
>> In function \u2018md5_process_block\u2019:
>> lto1: internal compiler error: Segmentation fault
>> Please submit a full bug report,
>> with preprocessed source if appropriate.
>> See <http://gcc.gnu.org/bugs.html> for instructions.
>> make: *** [/tmp/cc1Nc0QJ.ltrans0.ltrans.o] Error 1
>> lto-wrapper: make returned 2 exit status
>> lto-wrapper failedcollect2: ld returned 1 exit status
>
> Hmm, I used to get similar segfault in liblto-plugin build that got fixed
> incrementally since I comitted few fixes from last week last night.  Now I got
> clean profiledbootstrap build (with few local patches, but those are just to
> enable plugin by default now)
>
> By quick measurement unoptimize build of combine2.i reduces from 2.836s to
> 2.544s, 9.4% (on checking enabled compiler) and size by 6% compared to LTO
> bootstrapped cc1, so things seems to work as expected now.  -O2 build is about
> 6% faster.  This is consistent with my earlier tests.
>
> I configure as --enable-stage1-languages=c,lto --with-ld=/abuild/jh/trunk-install/bin/ld --with-build-config=bootstrap-lto
>
> I will try checking disabled compiler to possibly reproduce your segfault.
>

Please make sure that plugin isn't disabled.



-- 
H.J.