cannot use clang with gold without matching llvm-X.Y-dev package

[Dimitri John Ledkov]

I must install llvm-dev package to use gold plugin in clang. But clang does not depend on llvm-dev by default. Maybe it should?
---
ApportVersion: 2.5.1-0ubuntu2
Architecture: amd64
DistroRelease: Ubuntu 12.10
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
Package: llvm-3.0 3.0-9ubuntu1
PackageArchitecture: amd64
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm-256color
 PATH=(custom, user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 3.5.0-11.11-generic 3.5.2
Tags: quantal running-unity
Uname: Linux 3.5.0-11-generic x86_64
UpgradeStatus: Upgraded to quantal on 2012-01-04 (236 days ago)
UserGroups: adm admin cdrom dialout kvm libvirtd lp lpadmin plugdev sambashare sbuild vboxusers
---
ApportVersion: 2.5.1-0ubuntu2
Architecture: amd64
DistroRelease: Ubuntu 12.10
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
Package: llvm-3.0
PackageArchitecture: amd64
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm-256color
 PATH=(custom, user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 3.5.0-11.11-generic 3.5.2
Tags: quantal running-unity
Uname: Linux 3.5.0-11-generic x86_64
UpgradeStatus: Upgraded to quantal on 2012-01-04 (236 days ago)
UserGroups: adm admin cdrom dialout kvm libvirtd lp lpadmin plugdev sambashare sbuild vboxusers

[Dimitri John Ledkov (xnox)]

apport information

[Dimitri John Ledkov (xnox)]

apport information

[Felix Geyer (debfx)]

clang shouldn't depend on llvm-dev as llvm-defaults is not necessarily at the same version as clang.

[Dimitri John Ledkov (xnox)]

ok. Matching llvm-X.Y-dev then?

[Sylvestre Ledru (sylvestre)]

Please report this bug on Debian. I will have a look then.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Anders Kaseorg (andersk)]

llvm-X.Y-dev isn’t enough. clang really needs the /usr/lib/libLTO.so and /usr/lib/LLVMgold.so symlinks provided by the llvm-dev metapackage.

[Matthias Klose (doko)]

I don't think that would be a good idea. why can't clang use the corresponding shared libs?

[Anders Kaseorg (andersk)]

I dunno, I’m just explaining how it works now. clang doesn’t use these libs directly; rather, ‘clang -O4 -use-gold-plugin’ invokes the linker (which must be gold) with ‘ld -plugin /usr/lib/LLVMgold.so’. And LLVMgold.so has a shared library dependency on libLTO.so without an rpath.

(If you want my opinion, I think these libs belong somewhere other than llvm-*-dev entirely, since they’re needed by clang users and not just LLVM developers.)

[Sylvestre Ledru (sylvestre)]

Could you report this bug in Debian too ?

[Bram Geron (bgeron)]

This bug also appears when the user does not ask for link-time optimization.

bgeron@tinker:/tmp$ clang -O0 -Wno-unused-value -emit-llvm -o test.ll test.c
/usr/bin/ld: /usr/bin/../lib/LLVMgold.so: error loading plugin: /usr/bin/../lib/LLVMgold.so: cannot open shared object file: No such file or directory
clang: error: linker command failed with exit code 1 (use -v to see invocation)

I currently do not have llvm-dev installed.

[Bram Geron (bgeron)]

Wait, that actually makes half-sense. I wanted only the LLVM, but -emit-llvm seems to activate LTO as a side effect, unless the user specifies -S .