Fix rare shaping problems with Urdu and Arabic

* src/composite.c (fill_gstring_body): Clear unused slots of the
gstring.  (Bug#50951)

diff --git a/src/composite.c b/src/composite.c
index 22422cca090e0de21df8c8119b167155b677eeed..249d7587f6151125b872dcf5f12c7dc9391fccc2 100644 (file)
--- a/src/composite.c
+++ b/src/composite.c
@@ -876,7 +876,8 @@ fill_gstring_body (Lisp_Object gstring)
        }
       LGLYPH_SET_ADJUSTMENT (g, Qnil);
     }
-  if (i < LGSTRING_GLYPH_LEN (gstring))
+  len = LGSTRING_GLYPH_LEN (gstring);
+  for (; i < len; i++)
     LGSTRING_SET_GLYPH (gstring, i, Qnil);
 }