c-decl.c (grokdeclarator): Give zero-length arrays size zero.

        * c-decl.c (grokdeclarator): Give zero-length arrays size zero.
        Remove dead code.
        * c-typeck.c (push_init_level): Move checks for flexible array
        members and zero length arrays ...
        (pop_init_level): ... here.  Silently discard empty initializations.
        Remove dead code.
        * varasm.c (output_constructor): Update for sizeof change to
        zero-length arrays.

        * extend.texi (Zero Length): Clarify semantics.

        * gcc.dg/940510-1.c: Update expected error wording.
        * gcc.dg/array-2.c, gcc.dg/array-3.c, gcc.dg/array-4.c: New.

From-SVN: r38678

1 files changed, 19 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/array-4.c b/gcc/testsuite/gcc.dg/array-4.c
new file mode 100644
index 0000000..9396dec
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/array-4.c
@@ -0,0 +1,19 @@
+/* { dg-do run } */
+/* { dg-options "" } */
+
+/* Verify that GCC's extension to initialize a zero-length array
+   member works properly.  */
+
+extern void abort(void);
+extern void exit(int);
+
+struct f { int w; int x[0]; } f = { 4, { 0, 1, 2, 3 } };
+
+int main()
+{
+  int i;
+  for (i = 0; i < f.w; ++i)
+    if (f.x[i] != i)
+      abort ();
+  exit(0);
+}