We should mention this GNU C extension in the manual.
Ok?
2014-03-25 Marek Polacek <pola...@redhat.com>
PR c/37428
* doc/extend.texi (C Extensions): Mention variable-length arrays in
a structure/union.
diff --git gcc/doc/extend.texi gcc/doc/extend.texi
index 986cc94..b564ade 100644
--- gcc/doc/extend.texi
+++ gcc/doc/extend.texi
@@ -1592,6 +1592,18 @@ Jumping or breaking out of the scope of the array name
deallocates the
storage. Jumping into the scope is not allowed; you get an error
message for it.
+@cindex variable-length array in a structure
+As an extension, GCC accepts variable-length arrays as a member of
+a structure or a union. For example:
+
+@smallexample
+void
+foo (int n)
+@{
+ struct S @{ int x[n]; @};
+@}
+@end smallexample
+
@cindex @code{alloca} vs variable-length arrays
You can use the function @code{alloca} to get an effect much like
variable-length arrays. The function @code{alloca} is available in
Marek
