Hello! I am trying to use the TSan instrumented OCaml compiler (5.2.1), however I keep getting bogus source location information in the TSan traces (for example: <null>:216698500 instead of <filename>:<linenum> in a TSan report). I am on an arm m1 mac, and my systems C compiler is set to apple’s cla…

Disclaimer: I have limited knowledge on the subject. I was able to make it output the filenames by adding a line that forced the program to wait for input. But no line numbers. In any case, I’d advise you to run the sanitizer on a Linux box, since on apple silicon it crashes (at least in the code…

Yeah, I assumed the experience would be smoother on a Linux machine however I do not have one, and also the documentation states that my setup should be supported: TSan support for OCaml is currently available for the x86_64 architecture, on FreeBSD, Linux and macOS, and for the arm64 architecture…

Hi, Are those lines in OCaml code or C stubs? Is your executable compiled with debug info? (It should be the case if you build with Dune’s default dev profile.)

If you are able to put together a reproducer, I can have a look at it.

Hey! yes I could: here is a repo that I’ve been trying to get traces to print with line info ( GitHub - yosefAlsuhaibani/eio_race: domains in a pool modifying a `ref` ). In the repo I did: opam switch create 5.2.1+options --package ocaml-option-tsan opam install eio eio_main dune exec bin/main.exe I…

Thanks. Opam is being funny right now so I can’t try it out, but I will try to do this soon. The compiler has a number of tests for TSan’s behaviour. Unfortunately we are not running them regularly on a Mac at the moment. You can run them to see if they pass in your setup: git clone https://github…

Ran the commands as suggested, and ran the tests in the TSan dir and it seems like I fail 3 test cases List of failed tests: tests/tsan/exn_from_c.ml tests/tsan/exn_in_callback.ml tests/tsan/exn_reraise.ml and all three seem to fail in a similar way > Running action 5/8 (check-program…

Yes, this is a known flakiness issue that I haven’t had time to fix yet, but it’s minor. I’m realizing that running these tests like this does not show much, because the location information is ignored by the test. What you can do is running ./ocamltest/ocamltest (relative path from the repo root) …

I’m afraid it works for me WARNING: ThreadSanitizer: data race (pid=2293850) Write of size 8 at 0x7f9bbb715b08 by thread T1 (mutexes: write M0): #0 camlDune__exe__Main.incr_391 /workspace_root/bin/main.ml:9 (main.exe+0x1fe178) #1 camlEio__Executor_pool.fun_814 /workspace_root/lib_eio/exec…

TSan/Thread sanitizer instrumented OCaml not outputting source line info (macos)

Ecosystem

aw0lambda0lambda March 7, 2025, 3:27pm 7

Ocaml code; I did try building it with the initial default dev settings, but the issue persisted so I tried explicitly adding -g + -fsanitize=thread explicitly

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TSan/Thread sanitizer instrumented OCaml not outputting source line info (macos)

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