1367932 - Undefined symbol _res_9_init with rustc 1.190-nightly

Status: RESOLVED FIXED

(Firefox Build System :: General, defect)

Description

[Ralph Giles (:rillian)]

rustc 1.19.0-nightly (5b13bff52 2017-05-23) has an undefined symbol issue on macOS 10.7 native static-analysis and tc-cross debug builds. Native opt build is ok.

> INFO -  Undefined symbols for architecture x86_64:
> INFO -    "_res_9_init", referenced from:
> INFO -        __ZN3std3net11lookup_host17h4921acf881e7a50cE in libgkrust.a(std-438eba4cd7d88a45.0.o)

https://treeherder.mozilla.org/#/jobs?repo=try&revision=4b3efd185e85&selectedJob=102081909
https://treeherder.mozilla.org/logviewer.html#?job_id=102081909&repo=try&lineNumber=34834

Comment 1

[Mike Hommey [:glandium]]

That symbol is in -lresolv. And it presumably is a consequence of https://thesquareplanet.com/blog/the-story-of-a-rust-bug/

That raises the interesting question whether we actually want rust code to be using libc's dns resolution...

Comment 2

[Ralph Giles (:rillian)]

Nice. And indeed rustc tells us we should have linked with -lresolv.

> INFO -  note: library: resolv

Time to dust off that staticlib dependency-tracking patch.

Comment 3

[Jeff Muizelaar [:jrmuizel]]

Has it been dusted?

Comment 4

[Ralph Giles (:rillian)]

I has not. I've been trying to unblock mac stylo builds and haven't been able to look at it.

The basis is this hack I wrote for testing the mp4 parser's glue code: https://github.com/mozilla/mp4parse-rust/blob/master/mp4parse_capi/examples/Makefile#L22 Possibly also assisted by adding more convenient rustc output a la rust-lang/rust#31471.

That needs to be ported to config/rules.mk

Comment 5

[Ralph Giles (:rillian)]

This issue made it into rust 1.19.0-beta.1, which otherwise we build with:

 https://treeherder.mozilla.org/#/jobs?repo=try&revision=b175c6eacd78a4dce0427cab6ef2623844984e2a&selectedJob=105270190

We can work around by just adding -lresolv to the macOS build config.

Comment 6

[Tristan Bourvon]

I fixed it by adding -lresolv to the LDFLAGS on line 67 of toolkit/library/moz.build

I'm not certain I fully understand the problem so I'm not sure if this is the correct way to fix it either. Can anyone confirm this?
If that's the correct solution I can submit a patch.

Comment 7

[Ralph Giles (:rillian)]

I'm ok with the fix as a work-around. It seems to do no harm even with rust 1.18.0.

The correct fix is to teach the build system to parse the dependent library list out of the cargo output and append it to the link line of the corresponding final library or executable.

Per #1 we could also fix this particular instance of the bug by writing a shim around the Firefox resolver to replace the system api when linking rust-std into XUL, similar to what we do with allocators.

Comment 8

[Tristan Bourvon]

Attachment: Bug 1367932 - Fix compile errors with SA caused by missing -lresolv on macOS

This is a simple workaround, but it could be replaced by something cleaner
(see bugzilla).

Review commit: https://reviewboard.mozilla.org/r/150130/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/150130/

Comment 9

[Jonathan Chan [:jyc]]

Ran into this too, and with the workaround in Tristan's diff everything seems to work fine. Would be cool if this could be merged!

Comment 10

[Ralph Giles (:rillian)]

Comment on attachment 8878879 [details]
Bug 1367932 - Fix compile errors with SA caused by missing -lresolv on macOS

https://reviewboard.mozilla.org/r/150130/#review156754

::: toolkit/library/moz.build:68
(Diff revision 1)
>  
>      # This option should go away in bug 1290972, but we need to wait until
>      # Rust 1.12 has been released.
> +    # We're also linking against libresolv to solve bug 1367932.
>      if CONFIG['OS_ARCH'] == 'Darwin':
> -        LDFLAGS += ['-Wl,-no_compact_unwind']
> +        LDFLAGS += ['-Wl,-no_compact_unwind,-lresolv']

I would have gone with a separate `LDFLAGS` entry for `-lresolv` since the driver understands that, but this works.

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/c802a2225e3e
Fix compile errors with SA caused by missing -lresolv on macOS r=rillian

Comment 12

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/c802a2225e3e

Comment 13

[Emma Humphries ☕️🎸🧞‍♀️✨ (she/they) [:emceeaich] (Pacific Time) use needinfo]

Tristan, it looks like you are the assignee on this bug, but under a different email. Are you still working on this bug? If not, would you please unassign yourself?

Comment 14

[Firefox Bug Husbandry Bot]

Sorry for the spurious NI request, missed that this bug had been resolved.