[clang] [llvm] [clang][MBD] set up module build daemon infrastructure (PR #67562)

[Michael Spencer via cfe-commits]

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@@ -0,0 +1,25 @@
+// Check that a clang invocation can spawn and handshake with a module build daemon
+
+// RUN: %kill-process "-cc1modbuildd mbd-handshake"
+// RUN: rm -rf mbd-handshake %t
+// RUN: split-file %s %t
+
+//--- main.c
+int main() {return 0;}
+
+// RUN: %clang -fmodule-build-daemon=mbd-handshake -Rmodule-build-daemon %t/main.c &> %t/output-new || true
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Bigcheese wrote:

For longer lived connections the 15 second timeout would just kill the server anyway right now. I believe when Connor and I discussed this issue the plan was to also have timeouts for reading from clients that can close individual connections, and then exit the server when all clients are gone and there has been no activity for a set time.

I'm definitely concerned about landing anything that would have anyone running tests end up with zombie processes, so I think it's a requirement that any patches that land need to have robust timeout handling.

https://github.com/llvm/llvm-project/pull/67562