1654109 - Firefox binaries have Unix paths in codeview_pdb70_debug_info which breaks symbolication in WPA

Status: RESOLVED FIXED

(Firefox Build System :: Toolchains, defect)

Description

[Jeff Muizelaar [:jrmuizel]]

Previously, we'd have a path like: "z:\task_1581500222\build\src\obj-firefox\gfx\angle\targets\libGLESv2\libGLESv2.pdb"

Now we have a path like: /builds/worker/workspace/obj-build/gfx/angle/targets/libGLESv2/libGLESv2.pdb

This seems to break various programs on Windows that try to download the symbols (WPA) because they try to get the symbol using the full path instead of the just the file name.

Comment 1

[Jeff Muizelaar [:jrmuizel]]

FWIW, it looks like this change may have happened some time between February and now.

Comment 2

[Jeff Muizelaar [:jrmuizel]]

More specifically it looks like the change happened 19th or 20th of March

Comment 3

[Jeff Muizelaar [:jrmuizel]]

It looks like this can be fixed using /pdbaltpath which seems to be what Chromium does:
https://source.chromium.org/chromium/chromium/src/+/master:build/config/compiler/BUILD.gn;l=2239;drc=3d2056486ebe2f6d1c5fc24220d2021d1d7cf3ed

Comment 4

[Jeff Muizelaar [:jrmuizel]]

In fact it looks like %_PDB% is magic string to just use the basename of the pdb. So adding /pdbaltpath:%_PDB% should just work.

Comment 5

[Jeff Muizelaar [:jrmuizel]]

Glandium, is adding /pdbaltpath:%_PDB% practical?

Comment 6

[Mike Hommey [:glandium]]

You tell me. Doesn't it break debugging local builds?

Comment 7

[Jeff Muizelaar [:jrmuizel]]

Yeah, I guess it would. The alternatives are to pass a Windows like path to /pdbaltpath, move the pdbs so that we can get %_PDB% to work or fix lld to rewrite the path. What do you think is best?

Comment 8

[(Away)]

Could we set /pdbaltpath:%_PDB% only if the host is Linux?

Comment 9

[Jeff Muizelaar [:jrmuizel]]

That seems like it would work too.

Comment 10

[Mike Hommey [:glandium]]

if the host is not Windows, yes.

Comment 11

[(Away)]

Does this build behave as expected? https://treeherder.mozilla.org/#/jobs?repo=try&revision=81779930b3cffb1c1d716050f4cdc3cea70cbfe5

(Need to use https://symbols.mozilla.org/try for the symbol server)

Comment 12

[(Away)]

Jeff, heads up, the try push symbols are going to age out soon.

Comment 13

[Jeff Muizelaar [:jrmuizel]]

I'll try today.

Comment 14

[Jeff Muizelaar [:jrmuizel]]

Yep, symbols load in Windows Performance Analyzer with that try build

Comment 15

[(Away)]

Attachment: Use PDB basename in cross-compiled Windows builds

In cross-compiled Windows builds, our binaries embed PDB paths like /builds/worker/... which breaks some Windows tools that expect Windows-style paths. This patch sets -PDBALTPATH:%_PDB% which instructs the linker to emit only the basename. That's apparently enough that the tools can still find the right symbols.

Comment 16

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/82395607203e
Use PDB basename in cross-compiled Windows builds r=firefox-build-system-reviewers,mhentges

Comment 17

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/82395607203e