* PathLocks::lockPaths: don't allow reacquiring a lock we already

  hold.

1 files changed, 2 insertions, 4 deletions

diff --git a/src/libstore/pathlocks.cc b/src/libstore/pathlocks.cc
index 03ba4f212..821d4d02f 100644
--- a/src/libstore/pathlocks.cc
+++ b/src/libstore/pathlocks.cc
@@ -161,10 +161,8 @@ void PathLocks::lockPaths(const PathSet & _paths, const string & waitMsg)
 
         debug(format("locking path `%1%'") % path);
 
-        if (lockedPaths.find(lockPath) != lockedPaths.end()) {
-            debug(format("already holding lock on `%1%'") % lockPath);
-            continue;
-        }
+        if (lockedPaths.find(lockPath) != lockedPaths.end())
+            throw Error("deadlock: trying to re-acquire self-held lock");
 
         AutoCloseFD fd;