[glib/fix-gnulib-msvc-isnan: 18/37] gvalue: Static strings should not be copied

[Chun-wei Fan <fanchunwei src gnome org>]

commit ce7616e74884624f120d2f0d55e2387b9710d410
Author: Edward Hervey <edward centricular com>
Date:   Fri May 15 17:28:45 2020 +0200

    gvalue: Static strings should not be copied
    
    When doing copies of GValue backed by static strings, the contents should not be copied

 gobject/gvaluetypes.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)
---
diff --git a/gobject/gvaluetypes.c b/gobject/gvaluetypes.c
index 35b85c684..755ddeae1 100644
--- a/gobject/gvaluetypes.c
+++ b/gobject/gvaluetypes.c
@@ -271,7 +271,16 @@ static void
 value_copy_string (const GValue *src_value,
                   GValue       *dest_value)
 {
-  dest_value->data[0].v_pointer = g_strdup (src_value->data[0].v_pointer);
+  if (src_value->data[1].v_uint & G_VALUE_NOCOPY_CONTENTS)
+    {
+      dest_value->data[0].v_pointer = src_value->data[0].v_pointer;
+      dest_value->data[1].v_uint = src_value->data[1].v_uint;
+    }
+  else
+    {
+      dest_value->data[0].v_pointer = g_strdup (src_value->data[0].v_pointer);
+      dest_value->data[1].v_uint = src_value->data[1].v_uint;
+    }
 }
 
 static gchar*