interaction with dependency tracking and subdir-objects

[Robert Collins <robert dot collins at itdomain dot com dot au>]

The following:

AUTOMAKE_OPTIONS = subdir-objects
bin_PROGRAMS = foo
foo_SOURCES = $(top_srcdir)/main.c

is legal AFAIK, and while the $(top_srcdir) is somewhat redundant, it
could get used when including some common rules via an automake
include..

unfortunately it generates the following dependency file path:
.deps/$(top_srcdir)/main.Po, which can fail in VPATH builds.

as a result I'd like to propose that dependencies get placed in 
the same relative directory as the source file resides, not the same
directory as the Makefile.

ie for this case $(top_builddir)/.deps/main.c

thoughts?
Rob

#!/bin/sh

# Test for $(top_srcdir) with dependencies.

. $srcdir/defs || exit 1

cat >main.c <<EOF
int main() { return 0; }
EOF


cat >Makefile.am <<EOF
AUTOMAKE_OPTIONS = subdir-objects
bin_PROGRAMS = foo
foo_SOURCES = \$(top_srcdir)/main.c
EOF

cat >configure.in <<EOF
AC_INIT(main.c)
AC_CONFIG_AUX_DIR(.)
AM_INIT_AUTOMAKE(test_am, 1.0)
AC_PROG_CC
AM_PROG_CC_C_O
AC_OUTPUT(Makefile)
EOF

# Fail gracefully if no autoconf.
$needs_autoconf

# Likewise for gcc.
(gcc -v) > /dev/null 2>&1 || exit 77

touch README NEWS AUTHORS ChangeLog

mkdir build

# We use gcc and not gcc -traditional as the latter fails on some
# Linux boxes (Red Hat 5.1 in particular).
$ACLOCAL \
   && $AUTOCONF \
   && $AUTOMAKE -a || exit 1

cd build \
   && CC='gcc' ../configure \
   && $MAKE || exit 1