[llvm] [flang-rt] Fixes EXECUTE_COMMAND_LINE() status management and double buffering (PR #184285)

[Eugene Epshteyn via llvm-commits]

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@@ -400,8 +395,8 @@ TEST_F(ZeroArguments, ECLNotFoundCommandErrorSync) {
   (*command.get(), wait, exitStat.get(), cmdStat.get(), cmdMsg.get());
 #ifdef _WIN32
   CheckDescriptorEqInt<std::int64_t>(exitStat.get(), 1);
-  CheckDescriptorEqInt<std::int64_t>(cmdStat.get(), 6);
-  CheckDescriptorEqStr(cmdMsg.get(), "Invalid command lineXXXXXXX");
+  CheckDescriptorEqInt<std::int64_t>(cmdStat.get(), 0);
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eugeneepshteyn wrote:

Same as the above, "cmd.exe /c NotFoundCommand" returns status code of 1.

https://github.com/llvm/llvm-project/pull/184285