[LLVMdev] [cfe-dev] Unwind behaviour in Clang/LLVM

[Evgeniy Stepanov]

On Thu, Feb 13, 2014 at 5:39 PM, Renato Golin <renato.golin at linaro.org> wrote:
> On 13 February 2014 11:35, Evgeniy Stepanov <eugenis at google.com> wrote:
>> Unwind table index '.ARM.exidx' at offset 0x818 contains 4 entries:
>> 0x5d4 <main>: 0x1 [cantunwind]
>
> This is exactly what I meant.
>
>
>> because the latter prevent any unwinding, breaking
>> debuggers/profilers/sanitizers.
>
> In that case, my argument stands again.
>
>
>> As I understand, the right way to enable basic unwind through any
>> function (without emitting landing pands etc, unless they are needed
>> for something else) is -funwind-tables. I'm going to add that in the
>> driver for all sanitizers then.
>
> -funwind-tables are not yet understood by ARM, but it is for Dwarf EH.
> I plan on moving ARM to the same style as Dwarf, so you can assume it
> is correct.

Hm, I see that -funwind-tables on arm-linux-androideabi target
replaces this "cantunwind" with a proper unwind table.
Hence http://llvm-reviews.chandlerc.com/D2762.