Re: fix order of -L flags added for libtool dep libs

[Ralf Wildenhues]

Hi Alexandre,

* Alexandre Oliva wrote on Mon, Apr 04, 2005 at 08:57:43PM CEST:
> On Apr  4, 2005, Alexandre Oliva <address@hidden> wrote:
> 
> > Consider the following scenario:
> > We're building a package that introduces libraries libA and libB, such
> > that libA links with libB, and both link with a pre-installed libtool
> > library /old/libC.la
> 
> > A previous version of the package is already installed, providing
> > older, incompatible versions of libA and libB in say /old
> 
> > For this build, we're installing libA and libB in a separate location,
> > say /new.
> 
> > The problem here is that, when we relink libA for installation, we
> > start with tmp_libs="-lB -L/new" (it's in reverse order), and then we
> > add prepend -lC but *append* -L/old to tmp_libs.  Later on, when we
> > de-reverse it, we end up searching -L/old before -L/new, so we try to
> > link with the old -lB, and fail.

> Err...  Bad patch.  This one should do better.  We have to make sure
> we add the -L flag such that, after reordering, it shows up before the
> dep lib.  Doh!

I have a feeling we fixed this in branch-2-0 and maybe forgot to
backport.  In any case it would be good to have a test for this.

Could you be bothered to adapt the proposed test case below so that it
exposes the bug clearly?  It's not very portable yet, hacked up against
branch-1-5 and modeled roughly after your description above.

Regards,
Ralf

--- /dev/null   2005-04-04 11:53:15.417024464 +0200
+++ tests/linkorder.test        2005-04-05 09:22:40.585253968 +0200
@@ -0,0 +1,97 @@
+#! /bin/sh
+# linkorder.test - make sure that library linking order matches
+
+# Test script header.
+need_prefix=no
+if test -z "$srcdir"; then
+  srcdir=`echo "$0" | sed 's%/[^/]*$%%'`
+  test "$srcdir" = "$0" && srcdir=.
+  test "${VERBOSE+set}" != "set" && VERBOSE=yes
+fi
+. $srcdir/defs || exit 1
+
+: ${install=install}
+: ${mkdir_p="mkdir -p"}
+
+set -e -x
+
+rm -rf linkorder
+mkdir linkorder
+top_dir=`cd linkorder && pwd`
+prefix_old=$top_dir/old
+prefix_new=$top_dir/new
+srcdir=$top_dir/src
+
+mkdir $srcdir
+
+cat >$srcdir/c.c <<EOF
+int c = 1;
+EOF
+
+$libtool --mode=compile $CC -c $srcdir/c.c -o $srcdir/c.lo
+$libtool --mode=link $CC -o $srcdir/libcee.la $srcdir/c.lo -rpath 
$prefix_old/lib
+$mkdir_p $prefix_old/lib
+$libtool --mode=install $install $srcdir/libcee.la $prefix_old/lib/libcee.la
+
+cat >$srcdir/a.c <<EOF
+extern int c;
+extern int b_old();
+int a_old()
+{
+  return c + b_old();
+}
+EOF
+
+cat >$srcdir/b.c <<EOF
+extern int c;
+int b_old()
+{
+  return 1 + c;
+}
+EOF
+
+$libtool --mode=compile $CC -c $srcdir/a.c -o $srcdir/a.lo
+$libtool --mode=compile $CC -c $srcdir/b.c -o $srcdir/b.lo
+$libtool --mode=link $CC -o $srcdir/libb.la $srcdir/b.lo \
+       -L$prefix_old/lib -lcee -rpath $prefix_old/lib
+$libtool --mode=link $CC -o $srcdir/liba.la $srcdir/a.lo \
+       $srcdir/libb.la -L$prefix_old/lib -lcee -rpath $prefix_old/lib
+$libtool --mode=install $install $srcdir/libb.la $prefix_old/lib/libb.la
+$libtool --mode=install $install $srcdir/liba.la $prefix_old/lib/liba.la
+
+rm -rf $srcdir
+mkdir $srcdir
+
+cat >$srcdir/a.c <<EOF
+extern int c;
+extern int b_new();
+int a_new()
+{
+  return c + b_new();
+}
+EOF
+
+cat >$srcdir/b.c <<EOF
+extern int c;
+int b_new()
+{
+  return 1 + c;
+}
+EOF
+
+
+$libtool --mode=compile $CC -c $srcdir/a.c -o $srcdir/a.lo
+$libtool --mode=compile $CC -c $srcdir/b.c -o $srcdir/b.lo
+$libtool --mode=link $CC -o $srcdir/libb.la $srcdir/b.lo \
+       -L$prefix_old/lib -lcee -rpath $prefix_new/lib
+$libtool --mode=link $CC -o $srcdir/liba.la $srcdir/a.lo \
+       $srcdir/libb.la -L$prefix_old/lib -lcee -rpath $prefix_new/lib
+$mkdir_p $prefix_new/lib
+$libtool --mode=install $install $srcdir/libb.la $prefix_new/lib/libb.la
+$libtool --mode=install $install $srcdir/liba.la $prefix_new/lib/liba.la
+
+. $prefix_new/lib/liba.la
+case $dependency_libs  in *old*new*) exit 1;; esac
+
+rm -rf $top_dir
+exit 0
Index: tests/Makefile.am
===================================================================
RCS file: /cvsroot/libtool/libtool/tests/Makefile.am,v
retrieving revision 1.32.2.3
diff -u -r1.32.2.3 Makefile.am
--- tests/Makefile.am   26 Jan 2005 17:53:51 -0000      1.32.2.3
+++ tests/Makefile.am   5 Apr 2005 07:20:22 -0000
@@ -46,7 +46,7 @@
        pdemo-make.test pdemo-exec.test pdemo-inst.test \
        mdemo-conf.test mdemo-make.test mdemo2-conf.test \
        mdemo2-make.test mdemo2-exec.test \
-       func_extract_archives.test 
+       func_extract_archives.test linkorder.test
 
 
 if HAVE_CXX