[LLVMdev] Help with libLTO and clang

[John Criswell]

On 12/7/11 2:38 AM, Santosh Nagarakatte wrote:
> Hi all,
>
> I am testing  link time optimizations with clang  on linux x86_64
> machine running Ubuntu Maverick.
> I am using clang with llvm release-3.0
>
> I followed the instructions on http://llvm.org/docs/LinkTimeOptimization.html
>
> However, when I try to compile with one file being bitcode and other
> being native code exactly as shown in the documentation, I get the
> following errors
>
> clang a.o main.o -o main.out

Try adding the -use-gold-plugin command-line option to the clang compile 
and link lines.

-- John T.

>
> gives
>
> /usr/bin/ld: error: a.o:1:3: invalid character
> /usr/bin/ld: error: a.o:1:3: syntax error, unexpected $end
> /usr/bin/ld: error: a.o: not an object or archive
> /usr/bin/ld: main.o: in function main:main.c(.text+0x30): error:
> undefined reference to 'foo1'
> clang: error: linker command failed with exit code 1 (use -v to see invocation)
>
>
> I have the GOLD linker  installed in the system.
>
> /usr/bin/ld --version
>
> displays
>
> GNU gold (GNU Binutils for Ubuntu 2.21.0.20110327) 1.11
>
> Any suggestions?
>
> Santosh
>