From 7377195297e66c02e91caab700e7984e4c6a904a Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <e.dolstra@tudelft.nl>
Date: Sun, 29 Mar 2009 18:06:00 +0000
Subject: [PATCH] * With `--max-jobs 0', print a nicer error message than
 "Assertion   `!awake.empty()' failed."

---
 src/libstore/build.cc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/libstore/build.cc b/src/libstore/build.cc
index d80c67358..b448cc6b7 100644
--- a/src/libstore/build.cc
+++ b/src/libstore/build.cc
@@ -2550,8 +2550,12 @@ void Worker::run(const Goals & _topGoals)
         /* Wait for input. */
         if (!children.empty() || !waitingForAWhile.empty())
             waitForInput();
-        else
+        else {
+            if (maxBuildJobs == 0) throw Error(
+                "unable to start any build; either increase `--max-jobs' "
+                "or enable distributed builds");
             assert(!awake.empty());
+        }
     }
 
     /* If --keep-going is not set, it's possible that the main goal