[glib/ebassi/issue-2770] Empty values are not valid GParamSpec

[Emmanuele Bassi <ebassi src gnome org>]

commit ea3f17d598d550345e94e4571130e429443e91cb
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Sun Sep 25 14:20:24 2022 +0100

    Empty values are not valid GParamSpec
    
    The validate() vfunc for GParamSpecParam returns FALSE for empty GValue,
    which means the is_valid() vfunc should do the same.
    
    This avoids a segfault when calling g_param_value_is_valid() on a
    GParamSpecParam.
    
    Fixes: #2770

 gobject/gparamspecs.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/gobject/gparamspecs.c b/gobject/gparamspecs.c
index f17b3488b9..17b8606572 100644
--- a/gobject/gparamspecs.c
+++ b/gobject/gparamspecs.c
@@ -894,6 +894,9 @@ param_param_is_valid (GParamSpec   *pspec,
 {
   GParamSpec *param = value->data[0].v_pointer;
 
+  if (param == NULL)
+    return FALSE;
+
   return g_value_type_compatible (G_PARAM_SPEC_TYPE (param), G_PARAM_SPEC_VALUE_TYPE (pspec));
 }