commit 67afaf385afa5a2bcc6b7640d7cec6cd5d17863e
from: Russ Cox <rsc@swtch.com>
date: Mon Jul 11 00:35:23 2011 UTC

acme: allow :?regexp for backward search

Fixes issue 80.

R=rsc
http://codereview.appspot.com/4662088

commit - ff4512ee906ba02533eb86442ce95862a443f1d2
commit + 67afaf385afa5a2bcc6b7640d7cec6cd5d17863e
blob - aec850b88713c8ee54851ff111a8dc02b1767e9f
blob + 813fd19b181d666cd6a055304ee72a21ec9eec60
--- src/cmd/acme/look.c
+++ src/cmd/acme/look.c
@@ -776,6 +776,10 @@ openfile(Text *t, Expand *e)
 	else{
 		eval = TRUE;
 		r = address(TRUE, t, range(-1,-1), range(t->q0, t->q1), e->u.at, e->a0, e->a1, e->agetc, &eval, &dummy);
+		if(r.q0 > r.q1) {
+			eval = FALSE;
+			warning(nil, "addresses out of order\n");
+		}
 		if(eval == FALSE)
 			e->jump = FALSE;	/* don't jump if invalid address */
 	}