[cfe-dev] Option handling (support) of -fsanitize=use-after-scope

[Martin Liška via cfe-dev]

Hello.

I've been working on use-after-scope sanitizer enablement in the GCC compiler ([1]) and
as I've read following submit request ([2]), the LLVM compiler started to utilize following option:
-mllvm -asan-use-after-scope=1

My initial attempt was to introduce a new option value for -fsanitize option (which would make both LLVM and GCC
option compatible). Following the current behavior of the LLVM, I would have to add a new --param which would
lead to a divergence. Is the suggested approach alterable for LLVM community?

I would also suggest following default behavior:
- If -fsanitize=address or -fsanitize=kernel-address is enabled, the use-after-scope sanitization should be enabled
- Similarly, providing -fuse-after-scope should enable address sanitization (either use-space or kernel-space)

Thank you for feedback,
Martin

[1] https://gcc.gnu.org/ml/gcc-patches/2016-05/msg00468.html
[2] http://reviews.llvm.org/D19347