Add a Libtool patch from Debian that prevents implicit overlinking.

autogen.sh

@@ -33,20 +33,19 @@ cd "$script_dir"
 
 autoreconf -fvi || exit $?
 
-# The following is not needed as long as we do not patch libtool.m4:
-
-# # Patch libtool.m4:
-# for patch in \
-#   ; do
-#     echo "applying $patch"
-#     patch -p 1 --no-backup-if-mismatch --forward -r - -i $patch -d .
-#     # The program 'patch' exits with exitcode=1 if the patch has already been applied.
-#     # Consider this a normal scenario:
-#     exitcode=$?; if test $exitcode -ne 0 && test $exitcode -ne 1; then exit $exitcode; fi
-# done
-# autoconf -f || exit $?
-# # Reset libtool.m4 timestamps to avoid confusing make:
-# touch -r m4/ltversion.m4 m4/libtool.m4 || exit $?
+# Patch libtool.m4:
+for patch in \
+  contrib/000link_all_deplibs-patch/link_all_deplibs.patch \
+  ; do
+    echo "applying $patch"
+    patch -p 1 --no-backup-if-mismatch --forward -r - -i $patch -d .
+    # The program 'patch' exits with exitcode=1 if the patch has already been applied.
+    # Consider this a normal scenario:
+    exitcode=$?; if test $exitcode -ne 0 && test $exitcode -ne 1; then exit $exitcode; fi
+done
+autoconf -f || exit $?
+# Reset libtool.m4 timestamps to avoid confusing make:
+touch -r m4/ltversion.m4 m4/libtool.m4 || exit $?
 
 # Patch the rest of the files:
 for patch in \

contrib/000link_all_deplibs-patch/README.txt

+This patch is borrowed from the Debian project:
+http://deb.debian.org/debian/pool/main/libt/libtool/libtool_2.4.6-15.debian.tar.xz
+
+The comment for the patch in the aformentioned archive says:
+## Do not link against deplibs.  This is not needed for shared libs
+## on atleast ELF systems since those already know which libs they
+## need themself.  This seems to break a few things and will be fixed
+## in a better way in a future upstream version.

contrib/000link_all_deplibs-patch/link_all_deplibs.patch

+--- a/config/ltmain.sh
++++ b/config/ltmain.sh
+@@ -7568,7 +7568,10 @@ func_mode_link ()
+ 	case $pass in
+ 	dlopen) libs=$dlfiles ;;
+ 	dlpreopen) libs=$dlprefiles ;;
+-	link) libs="$deplibs %DEPLIBS% $dependency_libs" ;;
++	link)
++	  libs="$deplibs %DEPLIBS%"
++	  test "X$link_all_deplibs" != Xno && libs="$libs $dependency_libs"
++	  ;;
+ 	esac
+       fi
+       if test lib,dlpreopen = "$linkmode,$pass"; then
+--- a/m4/libtool.m4
++++ b/m4/libtool.m4
+@@ -4936,6 +4936,9 @@ m4_if([$1], [CXX], [
+       ;;
+     esac
+     ;;
++  linux* | k*bsd*-gnu | gnu*)
++    _LT_TAGVAR(link_all_deplibs, $1)=no
++    ;;
+   *)
+     _LT_TAGVAR(export_symbols_cmds, $1)='$NM $libobjs $convenience | $global_symbol_pipe | $SED '\''s/.* //'\'' | sort | uniq > $export_symbols'
+     ;;
+@@ -4998,6 +5001,9 @@ dnl Note also adjust exclude_expsyms for C++ above.
+   openbsd* | bitrig*)
+     with_gnu_ld=no
+     ;;
++  linux* | k*bsd*-gnu | gnu*)
++    _LT_TAGVAR(link_all_deplibs, $1)=no
++    ;;
+   esac
+ 
+   _LT_TAGVAR(ld_shlibs, $1)=yes
+@@ -5773,6 +5779,7 @@ _LT_EOF
+ 	if test yes = "$lt_cv_irix_exported_symbol"; then
+           _LT_TAGVAR(archive_expsym_cmds, $1)='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-soname $wl$soname `test -n "$verstring" && func_echo_all "$wl-set_version $wl$verstring"` $wl-update_registry $wl$output_objdir/so_locations $wl-exports_file $wl$export_symbols -o $lib'
+ 	fi
++	_LT_TAGVAR(link_all_deplibs, $1)=no
+       else
+ 	_LT_TAGVAR(archive_cmds, $1)='$CC -shared $libobjs $deplibs $compiler_flags -soname $soname `test -n "$verstring" && func_echo_all "-set_version $verstring"` -update_registry $output_objdir/so_locations -o $lib'
+ 	_LT_TAGVAR(archive_expsym_cmds, $1)='$CC -shared $libobjs $deplibs $compiler_flags -soname $soname `test -n "$verstring" && func_echo_all "-set_version $verstring"` -update_registry $output_objdir/so_locations -exports_file $export_symbols -o $lib'