[Bug rtl-optimization/64081] [5/6/7 Regression] r217827 prevents RTL loop unroll

[aldyh at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64081

Aldy Hernandez <aldyh at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |aldyh at gcc dot gnu.org

--- Comment #28 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
I am at commit 53ec6b3f003abd3528f988fa32a07cc084128563:

Author: pault <pault@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Sun Jan 18 22:01:29 2015 +0000

    2015-01-18  Andre Vehreschild  <vehre@gmx.de>
            Janus Weil <janus@gcc.gnu.org>

...

    git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@219827
138bc75d-0d04-0410-96
1f-82ee72b054a4

And have applied the patch in
https://gcc.gnu.org/ml/gcc-patches/2016-02/msg00421.html.

I am building on gcc119, which is AIX power8-aix 2 7 (AIX 7.2 I presume).

export CXX="g++ -std=gnu++98"
/source/gcc/configure \
--with-gmp=/opt/cfarm --with-cloog=no --with-ppl=no
--with-libiconv-prefix=/opt/cfarm --disable-libstdcxx-pch --enable-__cxa_atexit
\
    --enable-languages=c,c++ 
make -j16

I am building with -std=gnu++98, as that particular point in the branch has an
issue being built with gcc 6.1.0 which is what is on gcc119 (see bz#69959).

I am running into:

/home/aldyh/src/gcc/libstdc++-v3/configure[20782]: syntax error at line 46079 :
`;' unexpected
/home/aldyh/src/gcc/libstdc++-v3/configure[20782]: syntax error at line 19 :
`)' unexpected
Makefile:12556: recipe for target 'configure-stage1-target-libstdc++-v3' failed
make[2]: *** [configure-stage1-target-libstdc++-v3] Error 2
make[2]: Leaving directory '/home/aldyh/bld/bisect'
Makefile:17452: recipe for target 'stage1-bubble' failed

Are there any other particular tricks for bootstrapping GCC circa 219827 on
this AIX?  Are there any other configury or otherwise flags?