I had the misfortune to try cvs libtool on hppa2.0-hp-hpux10.20 with a
version of the unbundled cc that prints the following warning when +O3
is used with +Z,
cc: warning 8006: Do not use optimization levels higher than 2 to generate a
shared library if a user of that library may redefine a routine within that library
(8006)
Alas that warning makes AC_LIBTOOL_COMPILER_OPTION decide +Z is no
good.
If AC_LIBTOOL_COMPILER_OPTION just wants to know if the option is
accepted, then perhaps it could grep for it in the output, on the
assumption "Unknown option: -foo" or similar would result from a bad
one. That would avoid being tricked by informational messages, or
even perhaps by compiler advertising banners.
By way of a concrete suggestion,
* libtool.m4 (AC_LIBTOOL_COMPILER_OPTION): Look for the name
of the option in the output before rejecting it.
--- libtool.m4.old Mon Oct 8 10:27:14 2001
+++ libtool.m4 Mon Oct 8 10:30:11 2001
@@ -513,13 +513,14 @@
echo "$lt_simple_compile_test_code" > conftest.$ac_ext
if (eval $ac_compile 2>conftest.err) && test -s $ac_outfile; then
# The compiler can only warn and ignore the option if not recognized
- # So say no if there are warnings
- if test -s conftest.err; then
- # Append any errors to the config.log.
- cat conftest.err 1>&AS_MESSAGE_LOG_FD
- else
- $2=yes
- fi
+ # So say no if there are warnings mentioning the option
+ cat conftest.err 1>&AS_MESSAGE_LOG_FD
+ $2=yes
+ for lt_i in $3; do
+ if grep -- $lt_i conftest.err >/dev/null; then
+ $2=no
+ fi
+ done
fi
$rm conftest*
CFLAGS="$save_CFLAGS"
