[clang-tools-extra] c94ecf3 - [clangd] Fix a race

[Kadir Cetinkaya via cfe-commits]

Author: Kadir Cetinkaya
Date: 2021-02-24T12:15:16+01:00
New Revision: c94ecf3f81ca42a98b3b279a7b210b67715f1c41

URL: https://github.com/llvm/llvm-project/commit/c94ecf3f81ca42a98b3b279a7b210b67715f1c41
DIFF: https://github.com/llvm/llvm-project/commit/c94ecf3f81ca42a98b3b279a7b210b67715f1c41.diff

LOG: [clangd] Fix a race

Differential Revision: https://reviews.llvm.org/D97366

Added: 
    

Modified: 
    clang-tools-extra/clangd/unittests/ClangdLSPServerTests.cpp

Removed: 
    


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diff  --git a/clang-tools-extra/clangd/unittests/ClangdLSPServerTests.cpp b/clang-tools-extra/clangd/unittests/ClangdLSPServerTests.cpp
index 4542f7423a48..695ed89ae7f4 100644
--- a/clang-tools-extra/clangd/unittests/ClangdLSPServerTests.cpp
+++ b/clang-tools-extra/clangd/unittests/ClangdLSPServerTests.cpp
@@ -314,8 +314,14 @@ TEST_F(LSPTest, ModulesThreadingTest) {
     ~AsyncCounter() {
       // Verify shutdown sequence was performed.
       // Real modules would not do this, to be robust to no ClangdServer.
-      EXPECT_TRUE(ShouldStop) << "ClangdServer should request shutdown";
-      EXPECT_EQ(Queue.size(), 0u) << "ClangdServer should block until idle";
+      {
+        // We still need the lock here, as Queue might be empty when
+        // ClangdServer calls blockUntilIdle, but run() might not have returned
+        // yet.
+        std::lock_guard<std::mutex> Lock(Mu);
+        EXPECT_TRUE(ShouldStop) << "ClangdServer should request shutdown";
+        EXPECT_EQ(Queue.size(), 0u) << "ClangdServer should block until idle";
+      }
       Thread.join();
     }