add (char*) cast to discard const and suppress warning

diff --git a/lib/gvc/gvplugin.c b/lib/gvc/gvplugin.c
index 9ef7ae98e25cb50d90a751758700a3a438da2f2d..2e4aeaae05c973427709308921b61737f796aedb 100644 (file)
--- a/lib/gvc/gvplugin.c
+++ b/lib/gvc/gvplugin.c
@@ -136,7 +136,7 @@ gvplugin_library_t *gvplugin_library_load(char *path)
     }
     hndl = lt_dlopen (p);
     if (!hndl) {
-        agerr(AGWARN, lt_dlerror());
+        agerr(AGWARN, (char*)lt_dlerror());
         return NULL;
     }