[glib] gmacros.h: Add Private Macro _GLIB_DEFINE_AUTOPTR_CHAINUP

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

commit 696db7561560d9311dca93f0c849f96770f41d01
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Mon Feb 2 23:21:35 2015 +0800

    gmacros.h: Add Private Macro _GLIB_DEFINE_AUTOPTR_CHAINUP
    
    This is necessary as we are using _GLIB_AUTOPTR_TYPENAME and
    _GLIB_AUTOPTR_FUNC_NAME in gtype.h for G_DECLARE_DERIVABLE_TYPE and
    G_DECLARE_FINAL_TYPE, but _GLIB_AUTOPTR_TYPENAME and
    _GLIB_AUTOPTR_FUNC_NAME expand to nothing on non-GCC, causing builds on
    non-GCC to break, due to bad typedef and function definitions.
    
    This patch defines a new private macro which does what is needed on GCC
    builds and does nothing on non-GCC builds, thus fixing the build.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=743640

 glib/gmacros.h |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)
---
diff --git a/glib/gmacros.h b/glib/gmacros.h
index 58d34b5..62b61cb 100644
--- a/glib/gmacros.h
+++ b/glib/gmacros.h
@@ -380,6 +380,11 @@
 #define _GLIB_AUTOPTR_TYPENAME(TypeName)  TypeName##_autoptr
 #define _GLIB_AUTO_FUNC_NAME(TypeName)    glib_auto_cleanup_##TypeName
 #define _GLIB_CLEANUP(func)               __attribute__((cleanup(func)))
+#define _GLIB_DEFINE_AUTOPTR_CHAINUP(ModuleObjName, ParentName) \
+  typedef ModuleObjName *_GLIB_AUTOPTR_TYPENAME(ModuleObjName);                                          \
+  static inline void _GLIB_AUTOPTR_FUNC_NAME(ModuleObjName) (ModuleObjName **_ptr) {                     \
+    _GLIB_AUTOPTR_FUNC_NAME(ParentName) ((ParentName **) _ptr); }                                        \
+
 
 /* these macros are API */
 #define G_DEFINE_AUTOPTR_CLEANUP_FUNC(TypeName, func) \
@@ -399,7 +404,10 @@
 #define g_auto(TypeName) _GLIB_CLEANUP(_GLIB_AUTO_FUNC_NAME(TypeName)) TypeName
 
 #else /* not GNU C */
+/* this (dummy) macro is private */
+#define _GLIB_DEFINE_AUTOPTR_CHAINUP(ModuleObjName, ParentName)
 
+/* these (dummy) macros are API */
 #define G_DEFINE_AUTOPTR_CLEANUP_FUNC(TypeName, func)
 #define G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(TypeName, func)
 #define G_DEFINE_AUTO_CLEANUP_FREE_FUNC(TypeName, func, none)