[pygobject] setup.py: enable -Wdeclaration-after-statement

[Christoph Reiter <creiter src gnome org>]

commit 7ac4e21ac31419816a689907b3e9846f74d0c458
Author: Christoph Reiter <reiter christoph gmail com>
Date:   Wed Mar 21 14:31:56 2018 +0100

    setup.py: enable -Wdeclaration-after-statement

 gi/pygtype.c | 3 ++-
 setup.py     | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/gi/pygtype.c b/gi/pygtype.c
index 7ef59730..64e6f5d5 100644
--- a/gi/pygtype.c
+++ b/gi/pygtype.c
@@ -630,11 +630,12 @@ pyg_type_lookup(GType type)
 {
     GType      ptype = type;
     PyGTypeMarshal     *tm = NULL;
+    marshal_helper_data_e marshal_helper;
 
     if (type == G_TYPE_INVALID)
        return NULL;
 
-    marshal_helper_data_e marshal_helper = GPOINTER_TO_INT (
+    marshal_helper = GPOINTER_TO_INT (
        g_type_get_qdata(type, pyg_type_marshal_helper_key));
 
     /* If we called this function before with @type and nothing was found,
diff --git a/setup.py b/setup.py
index 12b385b9..0793a98d 100755
--- a/setup.py
+++ b/setup.py
@@ -727,7 +727,7 @@ def add_ext_warn_flags(ext, compiler, _cache={}):
             "-Wall",
             "-Warray-bounds",
             # "-Wcast-align",
-            # "-Wdeclaration-after-statement",
+            "-Wdeclaration-after-statement",
             # "-Wdouble-promotion",
             "-Wduplicated-branches",
             # "-Wduplicated-cond",