AC_LIBOBJ with file in subdirectory does not work

[Bruno Haible]

Hi,

When AC_LIBOBJ is used with a source file in a subdirectory, no problem
from autoconf's side, but a fatal error from automake occurs.

I'm using autoconf 2.65, automake 1.11.1.

How to reproduce:
1) Create a fresh empty directory.
   $ mkdir -p foo build-aux
2) Save these three files:
========================== configure.ac =======================
AC_INIT([dummy], [0.0])
AC_CONFIG_AUX_DIR([build-aux])
AM_INIT_AUTOMAKE
AC_CONFIG_HEADERS([config.h])
AC_CONFIG_SRCDIR([configure.ac])
AC_PROG_CC
AC_LIBOBJ([foo/bar])
AC_CONFIG_FILES([Makefile])
AC_OUTPUT
========================== Makefile.am ========================
AUTOMAKE_OPTIONS = 1.5 foreign no-dependencies
bin_PROGRAMS = bar
bar_SOURCES =
bar_LDADD = $(LIBOBJS)
========================== foo/bar.c ==========================
#include <stdio.h>
int main () {
  printf ("Hello world!\n");
  return 0;
}
===============================================================
3) $ aclocal
   $ autoconf
   $ autoheader
   $ automake -a -c -f
   configure.ac:9: required file `./foo/bar.c' not found
   $ echo $?
   1
4) Verify that the file is really there:
   $ ls -l ./foo/bar.c
   -rw-r--r-- 1 bruno users 76 25. Mai 01:56 ./foo/bar.c

Adding AC_CONFIG_LIBOBJ_DIR([.]) to configure.ac does not help.

Bruno