From 2ab29be70c99483dbd8cf12eece4d553c7f953f3 Mon Sep 17 00:00:00 2001
From: Shea Levy <shea@shealevy.com>
Date: Sun, 6 Nov 2011 07:03:14 +0000
Subject: [PATCH] Fix faulty reversion of my changes to
 unsafeDiscardOutputDependency

---
 src/libexpr/primops.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 70560302ea..09a653002f 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -989,7 +989,7 @@ static void prim_unsafeDiscardOutputDependency(EvalState & state, Value * * args
     PathSet context2;
     foreach (PathSet::iterator, i, context) {
         Path p = *i;
-        p = "~" + string(p, 1);
+        if (p.at(0) == '=') p = "~" + string(p, 1);
         context2.insert(p);
     }