ASAN uses a fast stack unwinder that relies on frame pointers. ASAN builds on TBPL are optimized, and at least based on the try pushed I've done, do not seem to have -fno-omit-frame-pointer, resulting in some useless stacks in LSAN reports I've been investigating. Locally, adding "ac_add_options --enable-profiling" to my mozconfig fixed the problem with the stacks. Maybe tying this to "ac_add_options --enable-address-sanitizer" is the way to go? I'm not entirely sure what is required for this, but it seems like it would require modifying /build/autoconf/frameptr.m4 . Decoder, is there anything you do in your ASAN runs to deal with this?

In IRC, decoder said he thought we already had profiling enabled for ASAN builds, so he'd be okay with something like this.

Thanks for the review! https://hg.mozilla.org/integration/mozilla-inbound/rev/a0ee12861380

try run: https://tbpl.mozilla.org/?tree=Try&rev=659d8f58b430