Created attachment 1071335 [details]
Objects to install in /tmp/objects/ for failing command to process

Here's a backtrace:

Program received signal SIGSEGV, Segmentation fault.
0x000000000048c074 in ppc_elf_reloc_type_class (info=0xc89c60, rel_sec=0x7ce1d8, rela=0x80000000) at ../../binutils-2.23.52.0.1/bfd/elf32-ppc.c:9356
9356      struct ppc_elf_link_hash_table *htab = ppc_elf_hash_table (info);
Missing separate debuginfos, use: debuginfo-install zlib-1.2.8-7.fc21.x86_64
(gdb) bt
#0  0x000000000048c074 in ppc_elf_reloc_type_class (info=0xc89c60, rel_sec=0x7ce1d8, rela=0x80000000) at ../../binutils-2.23.52.0.1/bfd/elf32-ppc.c:9356
#1  0x00000000004849ea in elf_link_sort_relocs (psec=<synthetic pointer>, info=0x78ad00 <link_info>, abfd=0x7ac5c0)
    at ../../binutils-2.23.52.0.1/bfd/elflink.c:8502
#2  bfd_elf_final_link (abfd=0x7ac5c0, info=0x78ad00 <link_info>) at ../../binutils-2.23.52.0.1/bfd/elflink.c:11394
#3  0x000000000041952e in ldwrite () at ../../binutils-2.23.52.0.1/ld/ldwrite.c:582
#4  0x00000000004037f5 in main (argc=129, argv=0x7fffffffdda8) at ../../binutils-2.23.52.0.1/ld/ldmain.c:400

Created attachment 1071358 [details]
Specfile for building RHEL-7.2 cross compilers

Here's the specfile for building the RHEL-7.2 cross binutils. Just add the sources from the regular RHEL-7.2 binutils package.

If only the x86_64 and s390x cross-compilers aren't required, near the top of the specfile find this bit:

%define build_rhel		1
%define build_powerpc64 	%{build_rhel}
%define build_powerpc64le 	%{build_rhel}
%define build_s390x 		%{build_rhel}
%define build_x86_64 		%{build_rhel}

Change build_rhel to 0 and build_powerpc64 to 1.  Don't bother with build_powerpc64le as it's redundant.

Created attachment 1071386 [details]
Altered version of bfd-ppc64le.patch

Created attachment 1071387 [details]
Updated spec file

Hi David,

  The problem is the bfd-ppc64le.patch file.  I tries to make powerpc64 specific changes to generic parts of the linker, but it was guarding these changes with a check for #ifdef __PPC__.  Unfortunately that symbol is only defined if the *host* compiler is a ppc64 compiler, ie only when building a native ppc64 linker.  If you are building a cross hosted ppc64 linker then __PPC__ is not defined, and the patches in bfd-ppc64le.patch do not work.

  I have uploaded a new patch file pfd-ppc64le.2.patch and a new spec file which includes it.  You will note that I have left the old bfd-ppc64le.patch file in the spec file.  This is just laziness on my part.  It was simpler to do this than to remove the bfd-pp64le.patch and create a new, replacement patch instead.

  Please try out the new patch and let me know how you get on.  Also please let me know if you would prefer it if I created a replacement patch for bfd-ppc64le.patch, rather than a supplemental patch.

Cheers
  Nick

Okay, I can build a ppc32 libgcc okay, but the ppc64 BE shared libgcc now fails with the linker SEGV'ing when called from collect2.  Using the following command upon a set of objects extracted into a directory from an archive I'll upload shortly:

/usr/bin/powerpc64-rhel72-linux-gnu-ld \
    --build-id --no-add-needed --eh-frame-hdr --hash-style=gnu \
    -V -shared \
    -m elf64ppc \
    -o ./libgcc_s.so.1.tmp \
    crti.o \
    crtbeginS.o \
    -L. \
    --soname=libgcc_s.so.1 \
    --version-script=libgcc.map \
    _muldi3_s.o \
    _negdi2_s.o \
    _lshrdi3_s.o \
    _ashldi3_s.o \
    _ashrdi3_s.o \
    _cmpdi2_s.o \
    _ucmpdi2_s.o \
    _clear_cache_s.o \
    _trampoline_s.o \
    __main_s.o \
    _absvsi2_s.o \
    _absvdi2_s.o \
    _addvsi3_s.o \
    _addvdi3_s.o \
    _subvsi3_s.o \
    _subvdi3_s.o \
    _mulvsi3_s.o \
    _mulvdi3_s.o \
    _negvsi2_s.o \
    _negvdi2_s.o \
    _ctors_s.o \
    _ffssi2_s.o \
    _ffsdi2_s.o \
    _clz_s.o \
    _clzsi2_s.o \
    _clzdi2_s.o \
    _ctzsi2_s.o \
    _ctzdi2_s.o \
    _popcount_tab_s.o \
    _popcountsi2_s.o \
    _popcountdi2_s.o \
    _paritysi2_s.o \
    _paritydi2_s.o \
    _powisf2_s.o \
    _powidf2_s.o \
    _powixf2_s.o \
    _powitf2_s.o \
    _mulsc3_s.o \
    _muldc3_s.o \
    _mulxc3_s.o \
    _multc3_s.o \
    _divsc3_s.o \
    _divdc3_s.o \
    _divxc3_s.o \
    _divtc3_s.o \
    _bswapsi2_s.o \
    _bswapdi2_s.o \
    _clrsbsi2_s.o \
    _clrsbdi2_s.o \
    _fixunssfsi_s.o \
    _fixunsdfsi_s.o \
    _fixunsxfsi_s.o \
    _fixsfdi_s.o \
    _fixdfdi_s.o \
    _fixxfdi_s.o \
    _fixtfdi_s.o \
    _fixunssfdi_s.o \
    _fixunsdfdi_s.o \
    _fixunsxfdi_s.o \
    _fixunstfdi_s.o \
    _floatdisf_s.o \
    _floatdidf_s.o \
    _floatdixf_s.o \
    _floatditf_s.o \
    _floatundisf_s.o \
    _floatundidf_s.o \
    _floatundixf_s.o \
    _floatunditf_s.o \
    _divdi3_s.o \
    _moddi3_s.o \
    _udivdi3_s.o \
    _umoddi3_s.o \
    _udiv_w_sdiv_s.o \
    _udivmoddi4_s.o \
    ibm-ldouble_s.o \
    tramp_s.o \
    ppc64-fp_s.o \
    addsf3_s.o \
    divsf3_s.o \
    eqsf2_s.o \
    gesf2_s.o \
    lesf2_s.o \
    mulsf3_s.o \
    negsf2_s.o \
    subsf3_s.o \
    unordsf2_s.o \
    fixsfsi_s.o \
    floatsisf_s.o \
    floatunsisf_s.o \
    adddf3_s.o \
    divdf3_s.o \
    eqdf2_s.o \
    gedf2_s.o \
    ledf2_s.o \
    muldf3_s.o \
    negdf2_s.o \
    subdf3_s.o \
    unorddf2_s.o \
    fixdfsi_s.o \
    floatsidf_s.o \
    floatunsidf_s.o \
    extendsfdf2_s.o \
    truncdfsf2_s.o \
    enable-execute-stack_s.o \
    unwind-dw2_s.o \
    unwind-dw2-fde-dip_s.o \
    unwind-sjlj_s.o \
    unwind-c_s.o \
    emutls_s.o \
    libgcc.a \
    ./libc-2.17.so \
    crtendS.o \
    crtn.o

Created attachment 1071813 [details]
Objects to install in /tmp/objects2/ for failing ppc64 BE command to process

I applied the patch to the binutils src that is part of the RHEL7.2 beta build. The result was the same,  ld core dumps sigsegv when trying to link libgcc...

I am trying to create  a cross toolchain on RHEL6.3 x86_64 targeted at powerpc64le

Created attachment 1072058 [details]
Revised additional patch

*sigh*  I forgot to check the 64-bit ppc case.  Sorry about that.  I have uploaded a revised version of the new patch which should make both 32-bit and 64-bit ppc work.

Cheers
  Nick

I can build the compiler now, thanks!

After applying this latest patch, I am now able to build the compiler for the ppc64le-redhat-linux target.  Thank you.

The new 7.3 binutils should avoid the need for the patches uploaded here and instead just work.  Changing to MODIFIED so that QE can test/verify.

Verified for build binutils-2.25.1-20.base.el7.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2016-2265.html