[LLVMdev] GCC/LLVM frame pointer incompatibility on ARM

[Jim Grosbach]

Having a different code path for prologue just for the sanitizers sounds pretty risky to me. That code is already strewn with conditional and modal stuff. Adding another variable to the permutations scares me. Is there really no alternative? Conditional code in the sanitizers that figure things out? LLDB and GDB have a very similar sort of problem for backtraces, including when debug info isn’t available. How do they solve it?

-Jim


> On Jul 18, 2014, at 8:01 AM, Renato Golin <renato.golin at linaro.org> wrote:
> 
> On 17 July 2014 21:08, Reid Kleckner <rnk at google.com> wrote:
>> Would they be willing to have a flag?  Would we be willing to have a flag?
> 
> That's a good question. Anything we do would be easier than wait for
> them to do anything, so if we decide to go with a flag, it should be
> us implementing.
> 
> 
>> Or should we conditionalize this on OS and say, on Linux, do the gcc thing,
>> and on OS X, do the LLVM thing?
> 
> I think you agree with me that both solutions are ugly, but I'd rather
> not make this default behaviour anywhere, so that only who needs it
> (sanitizers) turns it on with a flag.
> 
> cheers,
> --renato
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev