From c56cd90cc93898ce4633cebc6ec5e490eb10fce4 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Wed, 6 Jan 2016 22:07:59 +0100
Subject: [PATCH] daemon: When repairing, rebuild if there is no substituter.

---
 nix/libstore/build.cc | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/nix/libstore/build.cc b/nix/libstore/build.cc
index bbcb55a0b9..2f8b4dabba 100644
--- a/nix/libstore/build.cc
+++ b/nix/libstore/build.cc
@@ -3482,8 +3482,17 @@ void LocalStore::repairPath(const Path & path)
 
     worker.run(goals);
 
-    if (goal->getExitCode() != Goal::ecSuccess)
-        throw Error(format("cannot repair path `%1%'") % path, worker.exitStatus());
+    if (goal->getExitCode() != Goal::ecSuccess) {
+        /* Since substituting the path didn't work, if we have a valid
+           deriver, then rebuild the deriver. */
+        Path deriver = queryDeriver(path);
+        if (deriver != "" && isValidPath(deriver)) {
+            goals.clear();
+            goals.insert(worker.makeDerivationGoal(deriver, StringSet(), bmRepair));
+            worker.run(goals);
+        } else
+            throw Error(format("cannot repair path `%1%'") % path, worker.exitStatus());
+    }
 }