PATCH: Add x32 support to _LT_ENABLE_LOCK

[H.J. Lu]

Hi,

Here is a patch to update _LT_ENABLE_LOCK to support x32:

https://sites.google.com/site/x32abi/home

which is the 32bit ABI for x86-64.  Binutils 2.22 supports "-m elf32_x86_64"
for x32.


H.J.
---
2011-12-12  H.J. Lu  <hongjiu...@intel.com>

        * m4/libtool.m4 (_LT_ENABLE_LOCK): Support x32.

diff --git a/m4/libtool.m4 b/m4/libtool.m4
index 9c2574f..3639851 100644
--- a/m4/libtool.m4
+++ b/m4/libtool.m4
@@ -1321,7 +1321,14 @@ s390*-*linux*|s390*-*tpf*|sparc*-*linux*)
            LD="${LD-ld} -m elf_i386_fbsd"
            ;;
          x86_64-*linux*)
-           LD="${LD-ld} -m elf_i386"
+           case `/usr/bin/file conftest.o` in
+             *x86-64*)
+               LD="${LD-ld} -m elf32_x86_64"
+               ;;
+             *)
+               LD="${LD-ld} -m elf_i386"
+               ;;
+           esac
            ;;
          ppc64-*linux*|powerpc64-*linux*)
            LD="${LD-ld} -m elf32ppclinux"