commit 44eb2088299f10d45a1b3950285c3314217e0f44
from: Russ Cox <rsc@swtch.com>
date: Thu Aug 27 00:36:40 2015 UTC

mk: avoid infinite loop when targets are repeated

Fixes "mk -f /tmp/x.mk y x" or "mk -f /tmp/x.mk" where /tmp/x.mk is:

x y x: f
	echo hi

Change-Id: I7fa87dc4750c04fdba010b990c190722b432b333
Reviewed-on: https://plan9port-review.googlesource.com/1361
Reviewed-by: Russ Cox <rsc@swtch.com>

commit - 775cb933ecea6361717ef1def27b5d9e90c385fd
commit + 44eb2088299f10d45a1b3950285c3314217e0f44
blob - a40e9ded8078ffe24f17e9b41830f41c191d87fc
blob + ca14e9d6729ffdb77b96be00973af3f5e5f8af5c
--- src/cmd/mk/mk.h
+++ src/cmd/mk/mk.h
@@ -109,6 +109,7 @@ typedef struct Node
 #define		NORECIPE	0x0400
 #define		DELETE		0x0800
 #define		NOMINUSE	0x1000
+#define		ONLIST		0x2000
 
 typedef struct Job
 {
blob - 7993e091b69c77a7de0c30a28e0670ce4a1796cd
blob + 60325198981883364247b0bccec90ece6975ff46
--- src/cmd/mk/recipe.c
+++ src/cmd/mk/recipe.c
@@ -70,10 +70,15 @@ dorecipe(Node *node)
 			ww->next = newword(buf);
 			ww = ww->next;
 			if(n == node) continue;
+			if((n->flags&ONLIST) != 0)
+				continue;
+			n->flags |= ONLIST;
 			n->next = node->next;
 			node->next = n;
 		}
 	}
+	for(n = node->next; n; n = n->next)
+		n->flags &= ~ONLIST;
 	for(n = node; n; n = n->next)
 		if((n->flags&READY) == 0)
 			return(did);