PR c/24010

	* c.opt (Woverride-init): New.
	* c-opts.c (c_common_post_options): Default warn_override_init to
	extra_warnings.
	* c-typeck.c (add_pending_init, output_init_element): Warn for
	overriding initializers without side effects.
	* doc/invoke.texi (-Woverride-init): Document.
	(-Wextra): Update.

testsuite:
	* gcc.dg/Woverride-init-1.c, gcc.dg/Woverride-init-2.c,
	gcc.dg/Woverride-init-3.c: New tests.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@117334 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 18 insertions, 0 deletions

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index d5a3b6bac6b..6d7bc1e1eec 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -2876,6 +2876,12 @@ This warning can be independently controlled by
 @option{-Wmissing-field-initializers}.
 
 @item
+An initialized field without side effects is overridden when using
+designated initializers (@pxref{Designated Inits, , Designated
+Initializers}).  This warning can be independently controlled by
+@option{-Woverride-init}.
+
+@item
 A function parameter is declared without a type specifier in K&R-style
 functions:
 
@@ -3302,6 +3308,18 @@ attribute.
 @opindex Wno-overflow
 Do not warn about compile-time overflow in constant expressions.
 
+@item -Woverride-init
+@opindex Woverride-init
+@opindex W
+@opindex Wextra
+Warn if an initialized field without side effects is overridden when
+using designated initializers (@pxref{Designated Inits, , Designated
+Initializers}).
+
+This warning is included in @option{-Wextra}.  To get other
+@option{-Wextra} warnings without this one, use @samp{-Wextra
+-Wno-override-init}.
+
 @item -Wpacked
 @opindex Wpacked
 Warn if a structure is given the packed attribute, but the packed