scanner: Warn and ignore return annotations when there is no return value

Otherwise the .gir can contain invalid data which would
likely cause a crash at runtime.

https://bugzilla.gnome.org/show_bug.cgi?id=752044
Signed-off-by: Garrett Regier <garrett.regier@riftio.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/giscanner/maintransformer.py b/giscanner/maintransformer.py
index 872395a0..bb79a5b3 100644
--- a/giscanner/maintransformer.py
+++ b/giscanner/maintransformer.py
@@ -784,6 +784,12 @@ class MainTransformer(object):
             tag = block.tags.get(TAG_RETURNS)
         else:
             tag = None
+
+        if tag is not None and return_.type == ast.TYPE_NONE:
+            message.warn('%s: invalid return annotation' % (block.name,),
+                         tag.position)
+            tag = None
+
         self._apply_annotations_param_ret_common(parent, return_, tag)
 
     def _apply_annotations_params(self, parent, params, block):
@@ -871,7 +877,6 @@ class MainTransformer(object):
 
         if block:
             self._apply_annotations_annotated(signal, block)
-
             # We're only attempting to name the signal parameters if
             # the number of parameters (@foo) is the same or greater
             # than the number of signal parameters