[gentoo-amd64] Cross-compiling to x86 on gentoo-amd64 systems..

[Miguel Filipe]

Hi all,

I cannot cross-compile to x86 (gcc bla bla -m32) some applications on my
gentoo-amd64 system.

Basically, I need amd64 AND x86 version of mpich2 or openmpi..
But both fail to compile to -m32 in the "phase"... the linking phase..

openmpi fails in:


miguel@feynman ~/mpi/openmpi-1.0.2/ompi/mpi/cxx $ /bin/sh ../../../libtool
--tag=CXX --mode=link g++  -O3 -DNDEBUG -m32 -finline-functions -pthread
-export-dynamic -m32  -o libmpi_cxx.la -rpath /opt/openmpi-1.0.2-x86/lib
mpicxx.lo intercepts.lo comm.lo  -lm  -lutil -lnsl -lm
g++ -shared -nostdlib
/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/../../../../lib32/crti.o
/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/32/crtbeginS.o  .libs/mpicxx.o
.libs/intercepts.o .libs/comm.o  -lutil -lnsl
-L/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/32
-L/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5
-L/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/../../../../x86_64-pc-linux-gnu/lib
-L/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/../../../../lib32
-L/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/../../.. -L/lib/../lib32
-L/usr/lib/../lib32 /usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/libstdc++.so
-L/usr/x86_64-pc-linux-gnu/bin -L/usr/x86_64-pc-linux-gnu/lib
-L/usr/lib/gcc/x86_64-pc-linux-gnu/../../../x86_64-pc-linux-gnu/lib
-L/usr/lib/gcc/x86_64-pc-linux-gnu/../../../lib64 -L/lib/../lib64
-L/usr/lib/../lib64 -lm -lpthread -lc -lgcc_s_32
/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/32/crtendS.o
/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/../../../../lib32/crtn.o  -m32
-pthread -m32 -Wl,-soname -Wl,libmpi_cxx.so.0 -o .libs/libmpi_cxx.so.0.0.0
/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/libstdc++.so: could not read symbols:
File in wrong format
collect2: ld returned 1 exit status



mpich2 fails in:

ar cr ../../../lib/libmpich.a comm_compare.o comm_create.o comm_dup.o
comm_free.o comm_get_name.o comm_group.o comm_rank.o comm_size.o
comm_remote_group.o comm_remote_size.o comm_set_name.o comm_split.o
comm_test_inter.o intercomm_create.o intercomm_merge.o commutil.o
ar: ../../../lib/libmpich.a: File format not recognized
make[3]: *** [.libstamp0] Error 1
make[3]: Leaving directory `/home/miguel/mpi/mpich2-1.0.3/src/mpi/comm'

miguel@feynman ~/mpi/mpich2-1.0.3/src/mpi/comm $ file
../../../lib/libmpich.a
../../../lib/libmpich.a: current ar archive

ar cannot recognize the libmpich.a ar archive..









both cases seem to be cause by improper "multi-lib" support, is this
correct?

How can I address this issue?
Its really important to me to have a 32bit version of this...

ps.: my 10k lines C source code project compiles for amd64 and for x86 with
no problems.

Best regards to all!

-- 
Miguel Sousa Filipe