1078370 - Build error with clang 3.5 on Ubuntu 14.10: "arcfour-amd64-gas.s:87:1: error: DWARF2 only supports one section per compilation unit"

Status: NEW

(Firefox Build System :: General, defect)

Description

[Daniel Holbert [:dholbert]]

STR:
 1. Be running Ubuntu 14.10 (currently beta) and the "clang" package.
 2. Try to build mozilla-central, as an opt build. I'm using this one-line mozconfig:
> mk_add_options MOZ_OBJDIR=@TOPSRCDIR@/../obj-opt


ACTUAL RESULTS:
The following build error.
{
arcfour-amd64-gas.s:87:1: error: DWARF2 only supports one section per compilation unit
.section .note.GNU-stack,"",@progbits
^
../../coreconf/rules.mk:408: recipe for target '$OBJDIR/security/nss/lib/freebl/arcfour-amd64-gas.o' failed
make[8]: *** [$OBJDIR/opt/security/nss/lib/freebl/arcfour-amd64-gas.o] Error 1
}

I'm able to build successfully with clang 3.4 on the same system.

VERSION INFO:
I'm building mozilla-central changeset 0ed32d9a42d6 on up-to-date Ubuntu 14.10 (beta).

My clang 3.5 reports itself as:
{
Ubuntu clang version 3.5.0-4ubuntu2 (tags/RELEASE_350/final) (based on LLVM 3.5.0)
}

(Note that this is more bleeding edge than the supposedly-"clang 3.5" version in Ubuntu 14.04, which is based off an older llvm trunk snapshot, I believe)

Not sure if this belongs as a build-config bug, a NSS bug, or a clang bug; filing it under build-config for now.

Comment 1

[Mike Hommey [:glandium]]

http://llvm.org/bugs/show_bug.cgi?id=20879

Comment 2

[Daniel Holbert [:dholbert]]

Thanks! So, it's a clang bug, already fixed upstream, but the fix hasn't (yet) made it into the clang package on Ubuntu 14.10.

I'll resolve this when I notice the ubuntu package being fixed.

Comment 3

[Alex Xu]

in the meantime, how can this be worked around?

Comment 4

[Mike Hommey [:glandium]]

Downgrade clang.

Comment 5

[Mike Hommey [:glandium]]

Or, in fact, upgrade clang, since the upstream bug is "fixed" (for some value of fixed)

Comment 6

[Daniel Holbert [:dholbert]]

(In reply to Mike Hommey [:glandium] from comment #4)
> Downgrade clang.

In particular: "sudo apt-get install clang-3.4"

(In reply to Mike Hommey [:glandium] from comment #5)
> Or, in fact, upgrade clang, since the upstream bug is "fixed" (for some value of fixed)

The fix still hasn't made it to Ubuntu 14.10 "clang" package, BTW, so I don't think you can upgrade via Ubuntu's repos yet. (I just verified that it's still broken there on my up-to-date Ubuntu 14.10 system.)

So, to upgrade, I think you need to build clang yourself, or download updated binaries from somewhere else.

(http://llvm.org/apt/ seems to have nightly builds available for Ubuntu via a 3rd-party repo; I'd expect this to be fixed there, though it's probably somewhat unstable.)

Comment 8

[Nicholas Nethercote [inactive]]

> In particular: "sudo apt-get install clang-3.4"

That does nothing for me, other than tell me this:

> clang-3.4 is already the newest version.


> So, to upgrade, I think you need to build clang yourself, or download
> updated binaries from somewhere else.

I tried this, but current clang trunk fails to build Firefox due to a different problem. Argh.

Comment 9

[Daniel Holbert [:dholbert]]

Wait, are you saying you hit this bug, **when compiling with clang version 3.4**? Or do you just have clang 3.4 and 3.5 installed side-by-side?

Comment 10

[Daniel Holbert [:dholbert]]

(To clarify: on my Ubuntu system, at the time of comment 7, the repo-provided clang packages would only allow one version to be installed at a time. So, installing clang 3.4 would uninstall my repo-provided "clang" package (which had version 3.5). I'm pretty sure I didn't hit this bug after rebuilding with clang 3.4 at that point, but I might be misremembering.)

Comment 11

[Steffen Wilberg]

After updating Ubuntu to 14.10, "clang" was updated to version 3.5.
"sudo apt-get install clang-3.4" installed clang version 3.4 at "clang-3.4".
Try "clang --version" vs. "clang-3.4 --version".

To use clang-3.4, modify your .mozconfig like this:
export CC="clang-3.4 -fcolor-diagnostics"
export CXX="clang++-3.4 -fcolor-diagnostics"

This let me build mozilla-central successfully.

Comment 12

[Nicholas Nethercote [inactive]]

Like Steffen says, after running |sudo apt-get install clang-3.4|, |clang| is 3.5 and |clang-3.4| is 3.4.

Comment 13

[Olli Pettay [:smaug][[e-mail]]]

This happens now on Fedora 22 when building opt builds.

Comment 14

[Olli Pettay [:smaug][[e-mail]]]

gcc it is for now.

Comment 15

[Botond Ballo [:botond]]

I'm running into this but, strangely, only for optimized builds. Debug builds are fine.