[libFuzzer] clarify the limitation of fsanitize-coverage=trace-cmp
llvm-svn: 254337
diff --git a/clang/docs/SanitizerCoverage.rst b/clang/docs/SanitizerCoverage.rst
index efcb49e..f8ac1dc 100644
--- a/clang/docs/SanitizerCoverage.rst
+++ b/clang/docs/SanitizerCoverage.rst
@@ -275,6 +275,7 @@
void __sanitizer_cov_trace_switch(uint64_t Val, uint64_t *Cases);
This interface is a subject to change.
+The current implementation is not thread-safe and thus can be safely used only for single-threaded targets.
Output directory
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