[Fwd: fix -export-symbols for Linux [patch]]

[James Henstridge]

 I should probably have sent this mesasge here instead.

James.

-------- Original Message --------
Subject: fix -export-symbols for Linux [patch]
Date: Thu, 18 Jul 2002 00:14:05 +0800
From: James Henstridge <address@hidden>
To: address@hidden



Currently the -export-symbols and -export-symbols-regex link flags for 
libtool do not function correctly under Linux.

The non matched symbols still seem available for dynamic linking (as can 
be seen with nm -D).  Instead, it seems to be removing debug information 
which makes things harder to debug (it is using the 
--retain-symbols-file argument, which doesn't affect the exported 
symbols list).  From what I can tell, this will occur for any other 
platforms where libtool is using --retain-symbols-file.

I put together a little patch that makes libtool create a version script 
and use the --version-script link flag.  It is only set to activate for 
linux, because that is all I have been able to test it on.  For all I 
know, the change may be appropriate for the *) case.

From my testing so far, it seems to be working correctly.  Any chance 
of this getting applied and a new 1.4.x release being made?  It has been 
over 6 months since the last 1.4.x release, and there are known problems 
in 1.4.2.

James.

--
Email: address@hidden              | Linux.conf.au 2003 Call for Papers out
WWW:   http://www.daa.com.au/~james/ |   http://conf.linux.org.au/cfp.html





--
Email: address@hidden              | Linux.conf.au 2003 Call for Papers out
WWW:   http://www.daa.com.au/~james/ |   http://conf.linux.org.au/cfp.html


  This patch makes -export-symbols and -export-symbols-regex work under
  Linux.  It probably works under other architectures, but I can't test
  that; so it is only triggering for linux* now.

--- libtool-1.4.2/libtool.m4.expsyms    Mon May 27 12:33:14 2002
+++ libtool-1.4.2/libtool.m4    Wed Jul 17 23:05:33 2002
@@ -1399,10 +1399,27 @@
     wlarc=
     hardcode_direct=yes
     hardcode_shlibpath_var=no
     ;;
 
+  linux*)
+    if $LD --help 2>&1 | egrep ': supported targets:.* elf' > /dev/null; then
+      archive_cmds='$CC -shared $libobjs $deplibs $compiler_flags ${wl}-soname 
$wl$soname -o $lib'
+      archive_expsym_cmds='echo "{" > $output_objdir/$libname.ver;
+        echo "global:" >> $output_objdir/$libname.ver;
+       cat $export_symbols | while read symbol; do
+         echo "  \$symbol;" >> $output_objdir/$libname.ver;
+       done;
+        echo "local: *;" >> $output_objdir/$libname.ver;
+        echo "};" >> $output_objdir/$libname.ver~
+        $CC -shared $libobjs $deplibs $compiler_flags ${wl}-soname $wl$soname 
${wl}-version-script ${wl}$output_objdir/$libname.ver -o $lib~
+        rm -f $output_objdir/$libname.ver'
+    else
+      ld_shlibs=no
+    fi
+    ;;
+
   *)
     if $LD --help 2>&1 | egrep ': supported targets:.* elf' > /dev/null; then
       archive_cmds='$CC -shared $libobjs $deplibs $compiler_flags ${wl}-soname 
$wl$soname -o $lib'
       archive_expsym_cmds='$CC -shared $libobjs $deplibs $compiler_flags 
${wl}-soname $wl$soname ${wl}-retain-symbols-file $wl$export_symbols -o $lib'
     else