[Patch, ARM] Enable libsanitizer

[Konstantin Serebryany]

On Thu, Mar 28, 2013 at 12:07 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Thu, Mar 28, 2013 at 12:00:23PM +0400, Evgeniy Stepanov wrote:
>> We do it because newer versions of Android use PIE binaries, and,
>> combined with other specifics of address space on Linux/ARM, there is
>> no space for ASan shadow anywhere else. And it's faster.
>>
>> Zero-based shadow requires PIE. Non-zero-based requires non-PIE on
>> Android. Is it the same with QEMU? If so, we should switch to
>> zero-based for uniformity and performance.
>
> I don't think most of the arm-linux-gnueabi binaries are PIEs, so using
> zero shadow offset would be wrong on Linux.  If 1 << 29 works (e.g. prelink
> library area on linux-arm is 0x41000000 .. 0x50000000, so
> shadow of 0x20000000 .. 0x3fffffff is fine for that), IMHO we should use it.

Do we need two separate offsets for Linux/ARM and Android/ARM?
That's what we have in clang today.

--kcc

>
>         Jakub