[llvm] [ASAN] Make asan pass idempotent. (PR #99439)

[Vitaly Buka via llvm-commits]

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@@ -0,0 +1,56 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals all --version 5
+; This test checks in the second run, function is not instrumented again.
+; RUN: opt < %s -passes=asan,asan -S | FileCheck %s
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vitalybuka wrote:

It would be nice to have some generic approach, which will work regardless of constructors.

How about about Module::addModuleFlag("nosanitize") which will be set and checked by every sanitizer?

I am not sure if this require RFC on discourse. @nikic @efriedma-quic WDYT?

https://github.com/llvm/llvm-project/pull/99439