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

[Aiden Grossman 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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boomanaiden154 wrote:

Good point. I've used it within all of these functions to ensure that the file descriptor is properly closed upon exiting the function (especially with error conditions). Thanks for pointing this out! I hadn't heard about `make_scope_exit` before.

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