[PATCH] ltdl: set libltdl_cv_need_uscore to yes on OS/2

[KO Myung-Hun]

On OS/2, dlopen() does not support a program. So libltdl_cv_need_uscore
is set to unknown, but dlsym() requires an underscore prefix. So set
libltdl_cv_need_uscore to yes on OS/2 if lt_cv_sys_symbol_underscore is
yes and libltdl_cv_need_uscore is unknown.

* m4/ltdl.m4 (LT_FUNC_DLSYM_USCORE): set libltdl_cv_need_uscore to yes
on os2*.
---
 m4/ltdl.m4 | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/m4/ltdl.m4 b/m4/ltdl.m4
index eeb37ac..ce7b2b7 100644
--- a/m4/ltdl.m4
+++ b/m4/ltdl.m4
@@ -804,6 +804,11 @@ if test yes = "$lt_cv_sys_symbol_underscore"; then
            [libltdl_cv_need_uscore=no], [libltdl_cv_need_uscore=yes],
            [],                          [libltdl_cv_need_uscore=cross])
          LIBS=$save_LIBS
+         if test x"$libltdl_cv_need_uscore" = xunknown; then
+           case $host_os in
+             os2*) libltdl_cv_need_uscore=yes ;;
+           esac
+         fi
        ])
   fi
 fi
-- 
1.8.5.2