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, 28 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/Woverride-init-1.c b/gcc/testsuite/gcc.dg/Woverride-init-1.c
new file mode 100644
index 00000000000..29eca3095cd
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/Woverride-init-1.c
@@ -0,0 +1,28 @@
+/* Test for warnings for overriding designated initializers:
+   -Woverride-init.  Bug 24010.  */
+/* Origin: Joseph Myers <joseph@codesourcery.com> */
+/* { dg-do compile } */
+/* { dg-options "-Woverride-init" } */
+
+struct s { int a; int b; int c; };
+union u { char a; long long b; };
+
+struct s s0 = {
+  .a = 1,
+  .b = 2,
+  .a = 3, /* { dg-warning "initialized field overwritten|near init" } */
+  4, /* { dg-warning "initialized field overwritten|near init" } */
+  5
+};
+
+union u u0 = {
+  .a = 1,
+  .b = 2, /* { dg-warning "initialized field overwritten|near init" } */
+  .a = 3 }; /* { dg-warning "initialized field overwritten|near init" } */
+
+int a[5] = {
+  [0] = 1,
+  [1] = 2,
+  [0] = 3, /* { dg-warning "initialized field overwritten|near init" } */
+  [2] = 4
+};