* lib-ignore.m4 (gl_IGNORE_UNUSED_LIBRARIES): Don't use ldd, as

it's not portable and it doesn't work with cross-compiles.  Fix missing-$
typo in 'test "gl_cv_ignore_unused_libraries" ...' that prevented -zignore
from being used with Sun's C compiler.

diff --git a/m4/ChangeLog b/m4/ChangeLog
index 980c902..d7d0fbb 100644 (file)
--- a/m4/ChangeLog
+++ b/m4/ChangeLog
@@ -1,3 +1,11 @@
+2006-01-16  Paul Eggert  <eggert@cs.ucla.edu>
+
+       * lib-ignore.m4 (gl_IGNORE_UNUSED_LIBRARIES): Don't use ldd, as
+       it's not portable and it doesn't work with cross-compiles.
+       Problem reported by Bruno Haible.  Fix missing-$ typo in
+       'test "gl_cv_ignore_unused_libraries" ...' that prevented
+       -zignore from being used with Sun's C compiler.
+
 2006-01-12  Bruno Haible  <bruno@clisp.org>
 
        * ldd.m4: New file.

diff --git a/m4/lib-ignore.m4 b/m4/lib-ignore.m4
index 319cf98..a84ca16 100644 (file)
--- a/m4/lib-ignore.m4
+++ b/m4/lib-ignore.m4
@@ -12,31 +12,22 @@ AC_DEFUN([gl_IGNORE_UNUSED_LIBRARIES],
   AC_CACHE_CHECK([for flag to ignore unused libraries],
     [gl_cv_ignore_unused_libraries],
     [gl_cv_ignore_unused_libraries=none
-     AC_LINK_IFELSE([AC_LANG_PROGRAM()],
-       [gl_ldd_output0=`(ldd conftest$ac_exeext) 2>/dev/null` ||
-         gl_ldd_output0=])
-     if test "$gl_ldd_output0"; then
-       gl_saved_ldflags=$LDFLAGS
-       gl_saved_libs=$LIBS
-       LIBS="$LIBS -lm"
+     gl_saved_ldflags=$LDFLAGS
+     # Use long option sequences like '-z ignore' to test for the feature,
+     # to forestall problems with linkers that have -z, -i, -g, -n, etc. flags.
+     for gl_flags in '-Xlinker -z -Xlinker ignore' '-z ignore'; do
+       LDFLAGS="$gl_flags $LDFLAGS"
        AC_LINK_IFELSE([AC_LANG_PROGRAM()],
-        [gl_ldd_output1=`(ldd conftest$ac_exeext) 2>/dev/null` ||
-           gl_ldd_output1=])
-       if test "$gl_ldd_output1" && test "$gl_ldd_output0" != "$gl_ldd_output1"
-       then
-        for gl_flags in '-Xlinker -zignore' '-zignore'; do
-          LDFLAGS="$gl_flags $LDFLAGS"
-          AC_LINK_IFELSE([AC_LANG_PROGRAM()],
-            [if gl_ldd_output2=`(ldd conftest$ac_exeext) 2>/dev/null` &&
-                test "$gl_ldd_output0" = "$gl_ldd_output2"; then
-               gl_cv_ignore_unused_libraries=$gl_flags
-             fi])
-          LDFLAGS=$gl_saved_ldflags
-          test "gl_cv_ignore_unused_libraries" != none && break
-        done
-       fi
-       LIBS=$gl_saved_LIBS
-     fi])
+        [case $gl_flags in
+           '-Xlinker -z -Xlinker ignore')
+             # Shorten this ugly thing, for prettier 'make' output.
+              gl_cv_ignore_unused_libraries='-Xlinker -zignore';;
+           *)
+             gl_cv_ignore_unused_libraries=$gl_flags;;
+          esac])
+       LDFLAGS=$gl_saved_ldflags
+       test "$gl_cv_ignore_unused_libraries" != none && break
+     done])
 
   test "$gl_cv_ignore_unused_libraries" != none &&
     LDFLAGS="$LDFLAGS $gl_cv_ignore_unused_libraries"