From: Keith Randall <khr@golang.org>
Date: Wed, 6 Nov 2024 21:53:02 +0000 (-0800)
Subject: runtime/race: treat map concurrent access detection as a race detector hit
X-Git-Tag: go1.24rc1~459
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=fc5e8f2f6ba07f999a780848aa66da7d73083c1e;p=gostls13.git

runtime/race: treat map concurrent access detection as a race detector hit

Sometimes the runtime realizes there is a race before the race detector does.
Maybe that's a bug in the race detector? But we should probably handle it.

Update #70164
(Fixes? I'm not sure.)

Change-Id: Ie7e8bf2b06701368e0551b4a1aa40f6746bbddd8
Reviewed-on: https://go-review.googlesource.com/c/go/+/626036
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
---

diff --git a/src/runtime/race/race_test.go b/src/runtime/race/race_test.go
index 4fe61683eb..cbc90ea0bb 100644
--- a/src/runtime/race/race_test.go
+++ b/src/runtime/race/race_test.go
@@ -107,6 +107,11 @@ func processLog(testName string, tsanLog []string) string {
 			gotRace = true
 			break
 		}
+		if strings.Contains(s, "fatal error: concurrent map") {
+			// Detected by the runtime, not the race detector.
+			gotRace = true
+			break
+		}
 	}
 
 	failing := strings.Contains(testName, "Failing")
@@ -177,8 +182,11 @@ func runTests(t *testing.T) ([]byte, error) {
 	)
 	// There are races: we expect tests to fail and the exit code to be non-zero.
 	out, _ := cmd.CombinedOutput()
-	if bytes.Contains(out, []byte("fatal error:")) {
-		// But don't expect runtime to crash.
+	fatals := bytes.Count(out, []byte("fatal error:"))
+	mapFatals := bytes.Count(out, []byte("fatal error: concurrent map"))
+	if fatals > mapFatals {
+		// But don't expect runtime to crash (other than
+		// in the map concurrent access detector).
 		return out, fmt.Errorf("runtime fatal error")
 	}
 	return out, nil