New test ffi_2/regress_b_261224444_test is red on ASAN

[sstrickl]

There are new test failures on [vm/ffi] Fix FfiTrampolineData GC bug.

The tests

ffi_2/regress_b_261224444_test Crash (expected Pass)

are failing on configurations

dartk-asan-linux-release-x64

Example log:

--- Command "vm" (took 02.000648s):
DART_CONFIGURATION=ReleaseASANX64 out/ReleaseASANX64/dart --no-sound-null-safety -Dtest_runner.configuration=dartk-asan-linux-release-x64 --ignore-unrecognized-flags --packages=/b/s/w/ir/cache/builder/sdk/.dart_tool/package_config.json /b/s/w/ir/cache/builder/sdk/tests/ffi_2/regress_b_261224444_test.dart

exit code:
-6

stdout:
Closure: (int) => Pointer<Void>
106309030598656

stderr:
=================================================================
==14948==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 100 byte(s) in 1 object(s) allocated from:
    #0 0x55665a0bd1ee in malloc ../staging/llvm_build/tools/clang/stage2-bins/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/compiler-rt/lib/asan/asan_malloc_linux.cpp:69:3
    #1 0x7f11cee8622a  (<unknown module>)
    #2 0x7f11cc824b42  (<unknown module>)
    #3 0x7f11cc823f06  (<unknown module>)
    #4 0x7f11cc823d85  (<unknown module>)
    #5 0x7f11cc823cb7  (<unknown module>)
    #6 0x7f11cc822be6  (<unknown module>)
    #7 0x7f11cc82293a  (<unknown module>)
    #8 0x7f11cc8221e5  (<unknown module>)
    #9 0x7f11cee82f2b  (<unknown module>)
    #10 0x55665a59b39c in dart::DartEntry::InvokeCode(dart::Code const&, unsigned long, dart::Array const&, dart::Array const&, dart::Thread*) ../../out/ReleaseASANX64/../../runtime/vm/dart_entry.cc
    #11 0x55665a59ade7 in dart::DartEntry::InvokeFunction(dart::Function const&, dart::Array const&, dart::Array const&, unsigned long) ../../out/ReleaseASANX64/../../runtime/vm/dart_entry.cc:145:10
    #12 0x55665a5a0c8e in dart::DartEntry::InvokeFunction(dart::Function const&, dart::Array const&) ../../out/ReleaseASANX64/../../runtime/vm/dart_entry.cc:37:10
    #13 0x55665a5a0c8e in dart::DartLibraryCalls::HandleMessage(long, dart::Instance const&) ../../out/ReleaseASANX64/../../runtime/vm/dart_entry.cc:732:28
    #14 0x55665a61b237 in dart::IsolateMessageHandler::HandleMessage(std::__2::unique_ptr<dart::Message, std::__2::default_delete<dart::Message>>) ../../out/ReleaseASANX64/../../runtime/vm/isolate.cc:1428:15
    #15 0x55665a6af9db in dart::MessageHandler::HandleMessages(dart::MonitorLocker*, bool, bool) ../../out/ReleaseASANX64/../../runtime/vm/message_handler.cc:240:16
    #16 0x55665a6b0fe3 in dart::MessageHandler::TaskCallback() ../../out/ReleaseASANX64/../../runtime/vm/message_handler.cc:450:18
    #17 0x55665aac7a55 in dart::ThreadPool::WorkerLoop(dart::ThreadPool::Worker*) ../../out/ReleaseASANX64/../../runtime/vm/thread_pool.cc:158:15
    #18 0x55665aac8e9a in dart::ThreadPool::Worker::Main(unsigned long) ../../out/ReleaseASANX64/../../runtime/vm/thread_pool.cc:330:9
    #19 0x55665a8dc79f in dart::ThreadStart(void*) ../../out/ReleaseASANX64/../../runtime/vm/os_thread_linux.cc:154:5
    #20 0x7f11d03b86da in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x76da) (BuildId: 1f06001733b9be9478b105faf0dac6bdf36c85de)

SUMMARY: AddressSanitizer: 100 byte(s) leaked in 1 allocation(s).

--- Re-run this test:
python3 tools/test.py -n dartk-asan-linux-release-x64 ffi_2/regress_b_261224444_test

/cc @dcharkes

[dcharkes]

main() {
  // Ensure we have FfiTrampolineData in heap.
  final foo = DynamicLibrary.process()
      .lookup<NativeFunction<Pointer<Void> Function(IntPtr)>>("malloc")
      .asFunction<Pointer<Void> Function(int)>();
  print(foo);

  triggerGc();

  print(foo(100).address);
}

We're calling malloc and not freeing. 🙃