[llvm] [llvm-exegesis] Close file descriptors after use (PR #86584)

[Min-Yih Hsu via llvm-commits]

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@@ -317,6 +317,7 @@ class SubProcessFunctionExecutorImpl
     int CounterFileDescriptor = Counter->getFileDescriptor();
     Error SendError =
         sendFileDescriptorThroughSocket(WriteFD, CounterFileDescriptor);
+    close(WriteFD);
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mshockwave wrote:

should we use `make_scope_exit` to make sure this fd is closed no matter how we leave this function?

https://github.com/llvm/llvm-project/pull/86584