[llvm-dev] RFC: EfficiencySanitizer

[Renato Golin via llvm-dev]

On 20 April 2016 at 13:18, Yury Gribov <y.gribov at samsung.com> wrote:
> Not when dead store happens in an external DSO where compiler can't detect
> it (same applies for single references).

Do you mean the ones between the DSO and the instrumented code?
Because if it's just in the DSO itself, then the compiler could have
spotted it, too, when compiling the DSO.

I mean, of course there are cases line interprocedural dead-store
(call a function that changes A while changing A right after), but
that again, could be found at compilation time, given enough inlining
depth or IP analysis.

Also, if this is not something the compiler can fix, what is the point
of detecting dead-stores? For all the non-trivial cases the compiler
can't spot, most will probably arise from special situations where the
compiler is changing the code to expose the issue, and thus, the user
has little control over how to fix the underlying problem.

cheers,
--renato