From bd64f605435ed71a685ef2b2685425ff3e1cb8e4 Mon Sep 17 00:00:00 2001
From: shreyax <shreyax@google.com>
Date: Thu, 5 Apr 2018 11:46:08 -0700
Subject: Fix check-then-act race for some function potentially returning
 multiple targets.

PiperOrigin-RevId: 191774693
---
 .../java/com/google/devtools/build/lib/query2/engine/SomeFunction.java | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

(limited to 'src/main/java/com/google')

diff --git a/src/main/java/com/google/devtools/build/lib/query2/engine/SomeFunction.java b/src/main/java/com/google/devtools/build/lib/query2/engine/SomeFunction.java
index 4b07a99f07..995e288f29 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/engine/SomeFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/engine/SomeFunction.java
@@ -64,11 +64,10 @@ class SomeFunction implements QueryFunction {
           @Override
           public void process(Iterable<T> partialResult)
               throws QueryException, InterruptedException {
-            if (someFound.get() || Iterables.isEmpty(partialResult)) {
+            if (Iterables.isEmpty(partialResult) || !someFound.compareAndSet(false, true)) {
               return;
             }
             callback.process(ImmutableSet.of(partialResult.iterator().next()));
-            someFound.set(true);
           }
         });
     return env.whenSucceedsCall(
-- 
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