[glib: 3/4] gmacros: Document soft-deprecation of G_GNUC_NORETURN

[Philip Withnall <pwithnall src gnome org>]

commit 9cccc08b82d1df43c96e1fc1eb97ee6b1e2e30c5
Author: Philip Withnall <pwithnall endlessos org>
Date:   Wed Nov 25 11:37:06 2020 +0000

    gmacros: Document soft-deprecation of G_GNUC_NORETURN
    
    It still works, and deprecating it would be quite disruptive (as it’s
    used in headers), so amend the documentation to point people to
    `G_NORETURN` instead.
    
    Signed-off-by: Philip Withnall <pwithnall endlessos org>
    
    Helps: #994

 glib/gmacros.h | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/glib/gmacros.h b/glib/gmacros.h
index e5cd32eca..65f3738a6 100644
--- a/glib/gmacros.h
+++ b/glib/gmacros.h
@@ -423,6 +423,12 @@
  * It is used for declaring functions which never return. It enables
  * optimization of the function, and avoids possible compiler warnings.
  *
+ * Since 2.68, it is recommended that code uses %G_NORETURN instead of
+ * %G_GNUC_NORETURN, as that works on more platforms and compilers (in
+ * particular, MSVC and C++11) than %G_GNUC_NORETURN, which works with GCC and
+ * Clang only. %G_GNUC_NORETURN continues to work, so has not been deprecated
+ * yet.
+ *
  * Place the attribute after the declaration, just before the semicolon.
  *
  * |[<!-- language="C" -->