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

[Steven Wu 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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cachemeifyoucan wrote:

I don't think the current timeout implementation will work for a more complicated case than just a handshake (happy to prove wrong with an example).

For situation like: client sends handshake, server ack before timeout, client should send payload but died or killed, server is forever waiting for the payload.

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