decls must be constant.  big thanks to cinap for this one!

Reference: /n/atom/patch/applied/ccconstdcl
Date: Wed Apr 22 04:53:24 CES 2015
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/cc/dcl.c	Wed Apr 22 04:53:13 2015
+++ /sys/src/cmd/cc/dcl.c	Wed Apr 22 04:53:15 2015
@@ -381,8 +381,14 @@
 				diag(a, "initialization of incompatible pointers: %s\n%T and %T",
 					s->name, t, a->type);
 			}
-			if(a->op == OADDR)
+			if(a->op == OADDR) {
 				a = a->left;
+				goto gext;
+			}
+			if(a->type->etype == TIND) {
+				diag(a, "initializer is not a constant: %s", s->name);
+				return Z;
+			}
 			goto gext;
 		}