Trouble building latest svn head

[Dhruv Matani]

On Wed, Jul 25, 2012 at 7:16 PM, Ian Lance Taylor <iant@google.com> wrote:
> On Wed, Jul 25, 2012 at 5:37 PM, Dhruv Matani <dhruvbird@gmail.com> wrote:
>> Hello Ian,
>>
>> On Wed, Jul 25, 2012 at 5:09 PM, Ian Lance Taylor <iant@google.com> wrote:
>>
>>> This appears to be a problem with your C library.  On your system
>>> /usr/include/features.h does #include <bits/predefs.h>, but
>>> bits/predefs.h does not exist.  There isn't much GCC can do to help
>>> there.

yes, I'm in ubuntu 12.04.

>>>
>>> If you look at /usr/include/features.h you may find some other ideas.
>>
>> It seems that predefs.h does exist, but it resides at:
>> /usr/include/i386-linux-gnu/bits/ and not /usr/include/bits/
>>
>> Is there some hack that I can do (set some env. vars. maybe) to let
>> gcc search that path as well for includes?
>
> Oh, sorry, you are running a new version of Debian or Ubuntu.  They
> choose to move header files and libraries around in a way that breaks
> all existing GCC release.  Please complain to them.
>
> In the meantime, setting these environment variables may help:
>
> LIBRARY_PATH=/usr/lib/i386-linux-gnu
> C_INCLUDE_PATH=/usr/include/i386-linux-gnu
> CPLUS_INCLUDE_PATH=/usr/include/i386-linux-gnu

Thanks! This worked. I've come a long way - and since, the stage 2 & 3
comparison is failing for me.

Comparing stages 2 and 3
warning: gcc/cc1plus-checksum.o differs
warning: gcc/cc1-checksum.o differs
Bootstrap comparison failure!
gcc/gcc.o differs
gcc/plugin.o differs
make[2]: *** [compare] Error 1
make[2]: Leaving directory `/home/dhruvbird/projects/gcc-build'
make[1]: *** [stage3-bubble] Error 2
make[1]: Leaving directory `/home/dhruvbird/projects/gcc-build'
make: *** [all] Error 2

This is the command I am using to build:
$> ../gcc/configure --enable-languages=c,c++ --prefix=/opt/gcc-latest
--enable-shared --enable-threads=posix --enable-__cxa_atexit
--enable-clocale=gnu; make

Is there something wrong with this?

Someone on the internet has had success with performing a distclean
and running make again, and I am currently trying that:
http://www.linuxquestions.org/questions/linux-from-scratch-13/gcc-build-error-bootstrap-comparison-failure-692025/

However, if you know why this could be happening, please do let me know.

Regards,
-Dhruv.