[libcxx] [llvm] [XRay] Add bounds check before memcpy in readBinaryFormatHeader (PR #178499)

[Nikolas Klauser via llvm-commits]

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@@ -12,8 +12,8 @@
 # LLVM monorepo, and we make it a no-op unless the libc++ pipeline needs to be triggered.
 #
 
-# Set by buildkite
-: ${BUILDKITE_PULL_REQUEST_BASE_BRANCH:=}
+# Set by buildkite (may be unset for cross-fork PRs)
+: ${BUILDKITE_PULL_REQUEST_BASE_BRANCH:=main}
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philnik777 wrote:

Please don't make unrelated changes.

https://github.com/llvm/llvm-project/pull/178499