* ltmain.in: Mark duplicate libraries appearing in predeps and

postdeps as specialdeplibs.  Explain the whole plan.

diff --git a/ChangeLog b/ChangeLog
index dea32df48f5c7882e40a4b9d0577be4488ca620a..f45d4093f6d94ca4240c09f79a8c9209ed3f3184 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2001-04-11  Alexandre Oliva  <aoliva@redhat.com>
+
+       * ltmain.in: Mark duplicate libraries appearing in predeps and
+       postdeps as specialdeplibs.  Explain the whole plan.
+
 2001-04-11  Ossama Othman  <ossama@uci.edu>
 
        * config.guess: Updated to latest version.

diff --git a/ltmain.in b/ltmain.in
index e33fe4fe004997a948a870d62029248483054994..47db3501cae069b3d8480d31756cd9d1c928eb7d 100644 (file)
--- a/ltmain.in
+++ b/ltmain.in
@@ -1630,6 +1630,18 @@ EOF
 
     if test $linkmode = lib; then
       libs="$predeps $libs $compiler_lib_search_path $postdeps"
+
+      # Compute libraries that are listed more than once in $predeps
+      # $postdeps and mark them as special (i.e., whose duplicates are
+      # not to be eliminated).
+      pre_post_deps=
+      for pre_post_dep in $predeps $postdeps; do
+        case "$pre_post_deps " in
+       *" $pre_post_dep "*) specialdeplibs="$specialdeplibs $pre_post_deps" ;;
+       esac
+       pre_post_deps="$pre_post_deps $pre_post_dep"
+      done
+      pre_post_deps=
     fi
 
     deplibs=
@@ -2373,6 +2385,20 @@ EOF
            case $deplib in
             -L*) new_libs="$deplib $new_libs" ;;
             *)
+             # And here is the reason: when a library appears more
+             # than once as an explicit dependence of a library, or
+             # is implicitly linked in more than once by the
+             # compiler, it is considered special, and multiple
+             # occurrences thereof are not removed.  Compare this
+             # with having the same library being listed as a
+             # dependency of multiple other libraries: in this case,
+             # we know (pedantically, we assume) the library does not
+             # need to be listed more than once, so we keep only the
+             # last copy.  This is not always right, but it is rare
+             # enough that we require users that really mean to play
+             # such unportable linking tricks to link the library
+             # using -Wl,-lname, so that libtool does not consider it
+             # for duplicate removal.
               case " $specialdeplibs " in
               *" $deplib "*) new_libs="$deplib $new_libs" ;;
               *)