Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/compiler-rt/test/msan/errno.cc

@@ -0,0 +1,17 @@
+// RUN: %clangxx_msan -O0 %s -o %t && %run %t
+
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+int main()
+{
+  int x;
+  int *volatile p = &x;
+  errno = *p;
+  int res = read(-1, 0, 0);
+  assert(res == -1);
+  if (errno) printf("errno %d\n", errno);
+  return 0;
+}