On 6/30/20 6:52 PM, Harshit Sharma wrote:
Hey Martin,
Thanks for your reply. Actually I am trying to have a callback function
allowing gcc to fetch shadow offset from runtime code.
Ah, all right!
In order to make sure that my users have applied this patch before using asan feature, I
want to define a variable in gcc (could be an integer) which will be referenced by the
asan library in our source code. I think I used the wrong word 'emit' in my previous
post. The variable say "__asan_gccpatch_present" needs to be defined in gcc and
then referenced by our code (just like we do with functions such as __builtin_expect).
Then what about adding a new ASAN variable that you will directly access from
your source code?
What kind of interaction do you need? Or you can add a new ASAN builtin
(gcc/sanitizer.def), something like
__asan_poison_stack_memory that can be used in a user code?
Martin
Thanks,
Harshit
On Tue, Jun 30, 2020 at 12:34 AM Martin Liška <mli...@suse.cz
<mailto:mli...@suse.cz>> wrote:
On 6/30/20 7:55 AM, Harshit Sharma via Gcc wrote:
> Hello,
> I am working on a gcc patch for asan.
Hey.
Good to hear, what kind of feature is that?
> The patch is almost ready except one
> thing. To make sure that the user has applied this patch before using
asan
> feature, I want to declare an additional variable in gcc which is
reference
> by our source code so that if this patch is missing, the user gets an
error
> compiling the code because the reference to this variable will not be
> resolved.
A nice example can be emission of global variables that are used for
-fprofile-generate:
see gcc/tree-profile.c:194-202.
Let me know if it helps?
Martin
>
> I am still new to gcc development. So, can anyone tell me how can I make
> gcc emit this variable?
>
>
> Thanks,
> Harshit
>
