babl-fish-path: add debug print message when no fast paths were found

Messages get printed when the environment variable BABL_DEBUG_CONVERSIONS is
set, which also inhibits loading of babl fish cache.

diff --git a/babl/babl-fish-path.c b/babl/babl-fish-path.c
index 23e775712f7b5b5dc34d8cca48c21a75303dd564..7a7118438dd08253b5080b8adcd0a552f0518a18 100644 (file)
--- a/babl/babl-fish-path.c
+++ b/babl/babl-fish-path.c
@@ -341,6 +341,11 @@ babl_fish_path (const Babl *source,
     {
       babl_free (babl);
       babl_mutex_unlock (babl_format_mutex);
+
+      if (debug_conversions)
+        fprintf (stderr, "babl: no fast path for \"%s\" to \"%s\"\n",
+           babl_get_name (source),
+           babl_get_name (destination));
       return NULL;
     }