[llvm-branch-commits] [MSan] Pass -fsanitize-ignorelist to the instrumented libcxxabi (PR #83652)

[via llvm-branch-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-compiler-rt-sanitizer

Author: Alexander Richardson (arichardson)

<details>
<summary>Changes</summary>

This ensures that the MSan unit tests are able to pass with an
uninstrumented libunwind. We need to avoid instrumentation for
__gxx_personality_v0, which is part of the default msan_ignorelist.txt
that is installed into the resource directory. However, if we are trying
to test the just-built libraries, this global ignore list may not be
present yet, so we still instrument the function.

Arguably this function should not be on the default ignore list since it
is only a problem when building libcxxabi with MSan instrumentation and
without an instrumented libunwind, so maybe the logic should really be
part of the libcxxabi build. However, that could be done as a follow-up.

See 2f856a36e0b270b184051d10a18d4b4238b4c033 for more context.


---
Full diff: https://github.com/llvm/llvm-project/pull/83652.diff


1 Files Affected:

- (modified) compiler-rt/lib/msan/tests/CMakeLists.txt (+2-1) 


``````````diff
diff --git a/compiler-rt/lib/msan/tests/CMakeLists.txt b/compiler-rt/lib/msan/tests/CMakeLists.txt
index 0d43f432ab6a37..4f09f1e6a691fa 100644
--- a/compiler-rt/lib/msan/tests/CMakeLists.txt
+++ b/compiler-rt/lib/msan/tests/CMakeLists.txt
@@ -10,7 +10,8 @@ set(MSAN_LIBCXX_CFLAGS
   -fsanitize-memory-track-origins
   -fno-sanitize-memory-param-retval  # unittests test mostly this mode.
   -Wno-pedantic
-  -Xclang -fdepfile-entry=${COMPILER_RT_OUTPUT_DIR}/share/msan_ignorelist.txt
+    # Do not instrument __gxx_personality_v0 (part of libcxxabi)
+  -fsanitize-ignorelist=${COMPILER_RT_OUTPUT_DIR}/share/msan_ignorelist.txt
   )
 
 # Unittest sources and build flags.

``````````

</details>


https://github.com/llvm/llvm-project/pull/83652