1761327 - Debugging wasm file built via empscripten crashes the debugger

Status: NEW

(DevTools :: Debugger, defect, P2)

Description

[Alexandre Poirot [:ochameau]]

It looks like bug 1756951 introduced a crash in Debugger's findSources method when debugging WASM files built via emscripten. See bug 1719615 comment 31.

I'll provide a patch on top of bug 1719615 to easily reproduce the crash by running

$ ./mach mochitest --headless devtools/client/debugger/test/mochitest/browser_dbg-features-wasm.js

To really confirm it relates to bug 1756951,
here is a first try run without this bug's patches:
https://treeherder.mozilla.org/#/jobs?repo=try&revision=45c959d38824a643331565b7a159a4fa996db6a3
And another with them:
https://treeherder.mozilla.org/#/jobs?repo=try&revision=8b61a956e9dd502dfebe27b7add76623913cbc25

Comment 1

[Alexandre Poirot [:ochameau]]

Attachment: Bug 1761327 - [devtools] Make the WASM test use emscripten instead of WASI SDK.

Comment 2

[Alexandre Poirot [:ochameau]]

Both try runs reports failures, but only the second, with bug 1756951 crash.
The first try run fails because I forgot updating the binary breakpoint line.

Comment 3

[Alexandre Poirot [:ochameau]]

Lars, it looks like bug 1761327 makes the debugger crash with emscripten wasm files.
The crash stack trace looks slightly different from bug 1760627, but it may be related?
See 1719615 comment 31 for the stack trace.
Attachment 9269267 [details] helps easily reproduce the crash and note this is based on top of bug 1719615.

Comment 4

[Lars T Hansen [:lth]]

Yeah, Yury and I have been discussing that stack trace. There's a possibility it's related, but uncertain. We'll devote some time to this next week. Leaving the ni? for now.