libtool/tests/link-order2.at

# Hand crafted tests for GNU Libtool.                         -*- Autotest -*-
# Copyright 2006 Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.

# link-order2.test: make sure that depdepls are added right after
# the libs that pull them in: necessary at least for static linking
# and on systems where libraries do not link against other libraries,
# in order to do this: override a commonly used symbol in a commonly
# used library.

AT_SETUP([Link order of deplibs.])
AT_KEYWORDS([libtool])
LDFLAGS="$LDFLAGS -no-undefined"
libdir=`pwd`/inst/lib
bindir=`pwd`/inst/bin
mkdir inst inst/bin inst/lib

cat >a.c <<\EOF
/* pretend we have a better sine function */
double sin (double x) { return 0.0; }
EOF

cat >b.c <<\EOF
extern double sin (double);
double b (double x) { return sin (x); }
EOF

cat >main.c <<\EOF
#include <math.h>
extern double b (double);
extern double four;
double four = 4.0;
int main (void)
{
  /* The ! is to invert C true to shell true
   * The function b should call our sin (that returns 0) and not libm's
   * (in the latter case, b returns approximately 1)
   * the sqrt is to force linking against libm
   * the variable four is to prevent most compiler optimizations
   */
  return !( fabs (b (3.1415 / 2.)) < 0.01 && fabs (sqrt (four) - 2.) < 0.01 );
}
EOF

$LIBTOOL --mode=compile $CC $CPPFLAGS $CFLAGS -c a.c
$LIBTOOL --mode=compile $CC $CPPFLAGS $CFLAGS -c b.c
$CC $CPPFLAGS $CFLAGS -c main.c
for static in '' -static; do
  $LIBTOOL --mode=link $CC $CFLAGS $LDFLAGS $static -o liba.la a.lo -rpath $libdir
  $LIBTOOL --mode=link $CC $CFLAGS $LDFLAGS $static -o libb.la b.lo liba.la -rpath $libdir
  $LIBTOOL --mode=link $CC $CFLAGS $LDFLAGS -o main main.$OBJEXT libb.la -lm
  LT_AT_EXEC_CHECK([./main])
  # Now test that if we reverse the link order, the program fails.
  # The execution failure can only work on systems that actually have a libm.
  $LIBTOOL --mode=link $CC $CFLAGS $LDFLAGS -o wrong main.$OBJEXT -lm libb.la
  case $host_os in
  cygwin* | mingw* | pw32* | beos* ) ;;
  *) LT_AT_EXEC_CHECK([./wrong], [1]) ;;
  esac

  $LIBTOOL --mode=install cp liba.la $libdir/liba.la
  $LIBTOOL --mode=install cp libb.la $libdir/libb.la
  $LIBTOOL --mode=install cp main $bindir/main
  $LIBTOOL --mode=clean rm -f liba.la libb.la
  LT_AT_EXEC_CHECK([$bindir/main])
done


# Now the converse: if both the program and the library need libm, then
# it needs to be sorted last.  (TODO)

AT_CLEANUP