[compiler-rt] [Profile] Dump binary id to raw profiles on Windows. (PR #75618)

[David Li via llvm-commits]

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@@ -74,7 +74,14 @@ ValueProfNode *__llvm_profile_end_vnodes(void) { return &VNodesEnd; }
 ValueProfNode *CurrentVNode = &VNodesStart + 1;
 ValueProfNode *EndVNode = &VNodesEnd;
 
+uint64_t BuildIdLen = 16;
+COMPILER_RT_WEAK extern uint8_t __buildid[16];
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david-xl wrote:

Is this variable defined by lld?  Document the behavior.

https://github.com/llvm/llvm-project/pull/75618