[LLVMdev] Error with Gold Linker during LTO

[Daniel Stewart]

Glad to hear you can reproduce it. 

What I don't know is if this is a linker issue or an LLVM issue.

-----Original Message-----
From: Rafael Espíndola [mailto:rafael.espindola at gmail.com] 
Sent: Friday, May 30, 2014 3:58 PM
To: Daniel Stewart
Cc: LLVM Developers Mailing List
Subject: Re: Error with Gold Linker during LTO

Sorry, I had understood that the linker was crashing, not the generated program.

I can reproduce the issue now.

On 30 May 2014 15:48, Daniel Stewart <stewartd at codeaurora.org> wrote:
> So you see the issue as well in ARM? When doing a
>
> objdump -D weakMainO1.exe | grep -A 10 "<_ZN1C13caller_methodEv>:"
>
> I see:
>
> 00008b88 <_ZN1C13caller_methodEv>:
>     8b88:       e92d4800        push    {fp, lr}
>     8b8c:       e1a0b00d        mov     fp, sp
>     8b90:       e24dd008        sub     sp, sp, #8
>     8b94:       e58d0004        str     r0, [sp, #4]
>     8b98:       e59d0004        ldr     r0, [sp, #4]
>     8b9c:       ebffdd17        bl      0 <__preinit_array_end>
>     8ba0:       e1a0d00b        mov     sp, fp
>     8ba4:       e8bd4800        pop     {fp, lr}
>     8ba8:       e12fff1e        bx      lr
>
> where the bl 0 causes a seg fault.
>
> I'll check x86_64, but currently don't have that setup, so it'll take me a little bit of time to check.
>
> -----Original Message-----
> From: Rafael Espíndola [mailto:rafael.espindola at gmail.com]
> Sent: Friday, May 30, 2014 2:05 PM
> To: Daniel Stewart
> Cc: LLVM Developers Mailing List
> Subject: Re: Error with Gold Linker during LTO
>
>> clang++ -O1 -o weakMainO1.exe    -flto     -mcpu=cortex-a15 -mllvm
>> -debug-only=inline    -static weakMain.cpp weakImpl.o -v
>> -Wl,-plugin-opt=-debug-only=inline -Wl,-fuse-ld=gold 
>> -Wl,-plugin-opt=also-emit-llvm -Wl,-plugin-opt=obj-path=. >& O1.log
>
> Those command line options don't exist on trunk.
>
> The following works for me:
>
> $ clang++ -O0 weakImpl.cpp -o weakImpl.o -c
> $ clang++ -O1 -o weakMainO1.exe    -flto     -static weakMain.cpp weakImpl.o
>
> Do you also see the issue with x86_64?
>
> Cheers,
> Rafael
>