Re: AC_LIBTOOL_SYS_DYNAMIC_LINKER "gcc -print-search-dirs" problem

[Peter O'Gorman]

On Sep 13, 2006, at 11:34 PM, Bob Friesenhahn wrote:

> On Wed, 13 Sep 2006, Kate Minola wrote:
>
> > On my x86_64-unknown-linux-gnu system, the m4 macro
> > AC_LIBTOOL_SYS_DYNAMIC_LINKER in libtool.m4
> > uses "gcc -print-search-dirs" to set  sys_lib_search_path_spec.
> >
> > Unfortunately, -print-search-dirs lists -m32 library directories,
> > but gcc is in (default) -m64 mode on my system.  Consequently libtool
> > tries to link with the wrong library (32 bit when it should be  
> > using 64 bit).
> > The particular error message I get is
>
> I think that this is really a GCC bug.  I have the same problem  
> under Solaris.  Libtool should work around the GCC bug by detecting  
> 64-bit compilation and expanding the search path to look in the 64- 
> bit library directories first.

Hi Bob,
As far as I'm aware there is not going to be a fix for this in gcc,  
so yes, we need to fix it.
Perhaps something like:

echo "int main(){return 0;}" > conftest.c
search_path=`$CC $CFLAGS -c conftest.c 2>&1 | awk 'BEGIN {RS=" "} /^ 
[\"]?-L/ {sub ("-L","");print $0};'`
rm -f conftest.c conftest.o

Peter