commit 5ce2b6f5250fca0d4c80c1926c65744b4e094626
author Guillaume Chatelet <gchatelet@google.com> Tue Mar 30 15:27:46 2021 +0000
committer Copybara-Service <copybara-worker@google.com> Mon Apr 12 11:25:35 2021 -0700
tree 2d60adc2868e8c2fcea096bff26bac5d141bb2f2
parent 003026689a3f068393b66560dc56b62b59812c25

[libc] Fix msan/asan memcpy reentrancy

This is needed to prevent asan/msan instrumentation to redirect CopyBlock to `__asan_memcpy` (resp. `__msan_memcpy`).
These functions would then differ operation to `memcpy` which leads to reentrancy issues.

With this patch, `memcpy` is fully instrumented and covered by asan/msan.

If this turns out to be too expensive, instrumentation can be selectively or fully disabled through the use of the `__attribute__((no_sanitize(address, memory)))` annotation.

Differential Revision: https://reviews.llvm.org/D99598

GitOrigin-RevId: 77d81c2270c6221a430aac17c2c0aa73b39cc0d2