[compiler-rt] [compiler-rt] Mark more calls as blocking (PR #77789)

[Pavel Labath via llvm-commits]

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@@ -28,17 +28,17 @@ void *worker(void *main) {
 }
 
 void atfork() {
+  write(2, "in atfork\n", strlen("in atfork\n"));
   barrier_wait(&barrier);
   barrier_wait(&barrier);
-  write(2, "in atfork\n", strlen("in atfork\n"));
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labath wrote:

..because write now triggers the signal handler, causing the two strings to come out in opposite order

https://github.com/llvm/llvm-project/pull/77789