Open
Description
As originally reported here:
swiftlang/swift-corelibs-xctest#342
I get false leak positives when enabling LSan with Swift/Linux - according to helpful engineers there it seems to be due to Swift doing smart 'bit stuffing' of pointers.
It is worth noting that the same simple test does not give a false positive on macOS, so it may be that relevant code is platform-defined out (unnecessarily) for Linux.
I'm running with the 5.6 swift toolchain and related artifacts - this is reproduced on Ubuntu - running
gives the following from xctest:
ubuntu@swift:/home/xyzzy/swift-data-model$ swift test --sanitize address | swift demangle
Compiling plugin Swift-DocC...
Compiling plugin Swift-DocC Preview...
Building for debugging...
[1/3] Emitting module DataModelTests
[2/3] Compiling DataModelTests DataModelTests.swift
[5/8] /home/xyzzy/swift-data-model/.build/aarch64-unknown-linux-gnu/debug/swift-data-modelPackageTests.derived/runner.swift
[6/8] Wrapping AST for DataModelTests for debugging
[7/11] Compiling swift_data_modelPackageTests runner.swift
[8/11] Compiling swift_data_modelPackageTests DataModelTests.swift
[9/11] Emitting module swift_data_modelPackageTests
[12/13] Wrapping AST for swift-data-modelPackageTests for debugging
/usr/bin/ld.gold: warning: Cannot export local symbol '__asan_extra_spill_area'
[13/13] Linking swift-data-modelPackageTests.xctest
Build complete! (3.13s)
Test Suite 'All tests' started at 2022-04-27 18:31:07.420
Test Suite 'debug.xctest' started at 2022-04-27 18:31:07.423
Test Suite 'DataModelTests' started at 2022-04-27 18:31:07.423
Test Case 'DataModelTests.testThatDataModelFailsWriting' started at 2022-04-27 18:31:07.423
Test Case 'DataModelTests.testThatDataModelFailsWriting' passed (0.153 seconds)
Test Suite 'DataModelTests' passed at 2022-04-27 18:31:07.577
Executed 1 test, with 0 failures (0 unexpected) in 0.153 (0.153) seconds
Test Suite 'debug.xctest' passed at 2022-04-27 18:31:07.577
Executed 1 test, with 0 failures (0 unexpected) in 0.153 (0.153) seconds
Test Suite 'All tests' passed at 2022-04-27 18:31:07.577
Executed 1 test, with 0 failures (0 unexpected) in 0.153 (0.153) seconds
=================================================================
==6874==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 32 byte(s) in 1 object(s) allocated from:
#0 0xaaaad334683c in malloc /home/build-user/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:129:3
#1 0xffff9861db58 in operator new(unsigned long) (/lib/aarch64-linux-gnu/libstdc++.so.6+0x9fb58)
#2 0xffff997ce258 in swift::RefCounts<swift::RefCountBitsT<(swift::RefCountInlinedness)1> >::formWeakReference() (/usr/lib/swift/linux/libswiftCore.so+0x3ea258)
#3 0xffff9979e938 in swift_weakAssign (/usr/lib/swift/linux/libswiftCore.so+0x3ba938)
#4 0xffff98951168 in $s6XCTest9XCTWaiterC4wait3for7timeout12enforceOrder4file4lineAC6ResultOSayAA0A11ExpectationCG_SdSbs12StaticStringVSitF (/usr/lib/swift/linux/libXCTest.so+0x3f168)
#5 0xffff989514a8 in $s6XCTest9XCTWaiterC4wait3for7timeout12enforceOrder4file4lineAC6ResultOSayAA0A11ExpectationCG_SdSbs12StaticStringVSitFZ (/usr/lib/swift/linux/libXCTest.so+0x3f4a8)
#6 0xffff9893fda8 in $s6XCTest21awaitUsingExpectationyyyyYaKcKF (/usr/lib/swift/linux/libXCTest.so+0x2dda8)
#7 0xffff9893f37c in $s6XCTest0A4CaseC10invokeTestyyF (/usr/lib/swift/linux/libXCTest.so+0x2d37c)
#8 0xffff9893f1b0 in $s6XCTest0A4CaseC7performyyAA0A3RunCF (/usr/lib/swift/linux/libXCTest.so+0x2d1b0)
#9 0xffff989436d4 in $s6XCTestAAC3runyyF (/usr/lib/swift/linux/libXCTest.so+0x316d4)
#10 0xffff9894194c in $s6XCTest0A5SuiteC7performyyAA0A3RunCF (/usr/lib/swift/linux/libXCTest.so+0x2f94c)
#11 0xffff989436d4 in $s6XCTestAAC3runyyF (/usr/lib/swift/linux/libXCTest.so+0x316d4)
#12 0xffff9894194c in $s6XCTest0A5SuiteC7performyyAA0A3RunCF (/usr/lib/swift/linux/libXCTest.so+0x2f94c)
#13 0xffff989436d4 in $s6XCTestAAC3runyyF (/usr/lib/swift/linux/libXCTest.so+0x316d4)
#14 0xffff9894194c in $s6XCTest0A5SuiteC7performyyAA0A3RunCF (/usr/lib/swift/linux/libXCTest.so+0x2f94c)
#15 0xffff989436d4 in $s6XCTestAAC3runyyF (/usr/lib/swift/linux/libXCTest.so+0x316d4)
#16 0xffff9893dee0 in $s6XCTest7XCTMain_9arguments9observerss5NeverOSayAA0A4CaseCm04testF5Class_SaySS_yAHKctG8allTeststG_SaySSGSayAA0A11Observation_pGtF (/usr/lib/swift/linux/libXCTest.so+0x2bee0)
#17 0xffff9893da58 in $s6XCTest7XCTMainys5NeverOSayAA0A4CaseCm04testD5Class_SaySS_yAFKctG8allTeststGF (/usr/lib/swift/linux/libXCTest.so+0x2ba58)
#18 0xaaaad36ef024 in $s28swift_data_modelPackageTests6RunnerV4mainyyFZ /home/xyzzy/swift-data-model/.build/aarch64-unknown-linux-gnu/debug/swift-data-modelPackageTests.derived/runner.swift:10:9
#19 0xaaaad36ef098 in $s28swift_data_modelPackageTests6RunnerV5$mainyyFZ /home/xyzzy/swift-data-model/.build/aarch64-unknown-linux-gnu/debug/swift-data-modelPackageTests.derived/runner.swift:3:1
#20 0xaaaad36ef0b0 in main /home/xyzzy/swift-data-model/.build/aarch64-unknown-linux-gnu/debug/swift-data-modelPackageTests.derived/runner.swift
#21 0xffff98783d4c in __libc_start_main (/lib/aarch64-linux-gnu/libc.so.6+0x20d4c)
#22 0xaaaad32d3670 in _start (/home/xyzzy/swift-data-model/.build/aarch64-unknown-linux-gnu/debug/swift-data-modelPackageTests.xctest+0x91670)
SUMMARY: AddressSanitizer: 32 byte(s) leaked in 1 allocation(s).
ubuntu@swift:/home/xyzzy/swift-data-model$ The test is just empty (after having stripped it out piece by piece to nail down the leaker):
import XCTest
@testable import DataModel
@testable import DataModelExecutable
final class DataModelTests: XCTestCase {
override func setUp() {
super.setUp()
}
override func tearDown() {
super.tearDown()
}
func testThatDataModelFailsWriting() async throws {
}
}On macOS with the xctest running there with Xcode 13.3, I don't get any leak notified.
There are some relevant background discussion in the linked case above - let me know if you need additional information.