llvm dev - Jun 2010 - [LLVMdev] libLLVMgold.so: could not load plugin library

On 6/26/2010 10:30 AM, Rafael Espindola wrote:
>> So the gold and the LLVMgold are linked against the same libstdc++. I
am
>> using the gcc at /s/gcc-4.3.1/i386_rhel5/bin to compile the LLVM chain.
> Can you run llvm-gcc again with -Wl,-debug? This will show the linker
> line being used. You can then run gdb on it. Try to find what error is
> dlopen reporting. I wonder if gold is calling perror or not when
> dlopen fails (assuming it is dlopen that is failing).
The -Wl,-debug result is like this:
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld
-plugin 
$LLVMGCCPREFIX/libexec/gcc/i686-pc-linux-gnu/4.2.1/libLLVMgold.so 
-plugin-opt=as=as --eh-frame-hdr -m elf_i386 -dynamic-linker 
/lib/ld-linux.so.2 /usr/lib/crt1.o /usr/lib/crti.o 
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/crtbegin.o 
-L$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1 
-L$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../.. 
/tmp/ccnyauaa.o -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc 
--as-needed -lgcc_s --no-as-needed 
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/crtend.o /usr/lib/crtn.o
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
error: 
$LLVMGCCPREFIX/libexec/gcc/i686-pc-linux-gnu/4.2.1/libLLVMgold.so: could 
not load plugin library
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
error: /tmp/ccnyauaa.o:1:3: invalid character
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
error: /tmp/ccnyauaa.o:1:3: syntax error, unexpected $end
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
error: /tmp/ccnyauaa.o: not an object or archive
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
/usr/lib/crt1.o:(.text+0x18): error: undefined reference to 'main'

What should I do on gdb?

> The -Wl,-debug result is like this:
>
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld
> -plugin $LLVMGCCPREFIX/libexec/gcc/i686-pc-linux-gnu/4.2.1/libLLVMgold.so
> -plugin-opt=as=as --eh-frame-hdr -m elf_i386 -dynamic-linker
> /lib/ld-linux.so.2 /usr/lib/crt1.o /usr/lib/crti.o
> $LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/crtbegin.o
> -L$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1
> -L$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../.. /tmp/ccnyauaa.o
> -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s
> --no-as-needed $LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/crtend.o
> /usr/lib/crtn.o
>
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
> error: $LLVMGCCPREFIX/libexec/gcc/i686-pc-linux-gnu/4.2.1/libLLVMgold.so:
> could not load plugin library
>
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
> error: /tmp/ccnyauaa.o:1:3: invalid character
>
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
> error: /tmp/ccnyauaa.o:1:3: syntax error, unexpected $end
>
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
> error: /tmp/ccnyauaa.o: not an object or archive
>
$LLVMGCCPREFIX/lib/gcc/i686-pc-linux-gnu/4.2.1/../../../../i686-pc-linux-gnu/bin/ld:
> /usr/lib/crt1.o:(.text+0x18): error: undefined reference to 'main'
>
> What should I do on gdb?
>
Try to run just that ld command first. Same error message? Run in in
gdb and set a breakpoint just before gold tries to load the plugin.
Sorry, I am really out of ideas on what is going wrong here...

Cheers,
-- 
Rafael Ávila de Espíndola

On 6/27/2010 10:35 PM, Rafael Espindola wrote:
> Try to run just that ld command first. Same error message? Run in in
> gdb and set a breakpoint just before gold tries to load the plugin.
> Sorry, I am really out of ideas on what is going wrong here...
It is the same error message .

Can you tell me which gcc version are you using to compile the llvm 
chain, and also the binutils svn version number?

I noticed the dlopen is inside /lib/ld-linux.so.2, and my version of 
glibc is 2.5, is this too old?

Thanks.