gtk-demo: Fix an off-by-one error

This was found by the asan build in our ci.

diff --git a/demos/gtk-demo/unicode-names.c b/demos/gtk-demo/unicode-names.c
index 6c4f21924ab1da41aca63ef149238a3f6e69f09f..745e1b2db578ebcc9cd759ecd92008fd4e0c25f6 100644 (file)
--- a/demos/gtk-demo/unicode-names.c
+++ b/demos/gtk-demo/unicode-names.c
@@ -100,7 +100,7 @@ get_break_type_name (GUnicodeBreakType type)
 const char *
 get_combining_class_name (int cclass)
 {
-  const char *classes[255] = { 0, };
+  const char *classes[256] = { 0, };
 
   classes[0] = "Not Reordered";
   classes[1] = "Overlay";