1 files changed, 118 insertions, 0 deletions
diff --git a/test/sanitizer_common/TestCases/Linux/allocator_fork_no_hang.cc b/test/sanitizer_common/TestCases/Linux/allocator_fork_no_hang.cc
new file mode 100644
index 000000000..d159d85ee
--- /dev/null
+++ b/test/sanitizer_common/TestCases/Linux/allocator_fork_no_hang.cc
@@ -0,0 +1,118 @@
+// https://github.com/google/sanitizers/issues/774
+// Test that sanitizer allocator is fork-safe.
+// Run a number of threads that perform memory allocation/deallocation, then fork
+// and verify that malloc/free do not deadlock in the child process.
+
+// RUN: %clangxx -std=c++11 -O0 %s -o %t
+// RUN: ASAN_OPTIONS=detect_leaks=0 %run %t 2>&1 | FileCheck %s
+
+// Fun fact: if test output is redirected to a file (as opposed to
+// being piped directly to FileCheck), we may lose some "done"s due to
+// a kernel bug:
+// https://lkml.org/lkml/2014/2/17/324
+
+// UNSUPPORTED: tsan
+
+// Flaky on PPC64.
+// UNSUPPORTED: powerpc64-target-arch
+// UNSUPPORTED: powerpc64le-target-arch
+
+#include <pthread.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/time.h>
+#include <signal.h>
+#include <errno.h>
+
+int done;
+
+void *worker(void *arg) {
+  while (true) {
+    void *p = malloc(4);
+    if (__atomic_load_n(&done, __ATOMIC_RELAXED))
+      return 0;
+  }
+  return 0;
+}
+
+// Run through malloc/free in the child process.
+// This can deadlock on allocator cache refilling.
+void child() {
+  for (int i = 0; i < 10000; ++i) {
+    void *p = malloc(4);
+  }
+  write(2, "done\n", 5);
+}
+
+void test() {
+  const int kThreads = 10;
+  pthread_t t[kThreads];
+  for (int i = 0; i < kThreads; ++i)
+    pthread_create(&t[i], NULL, worker, (void*)(long)i);
+  usleep(100000);
+  pid_t pid = fork();
+  if (pid) {
+    // parent
+    __atomic_store_n(&done, 1, __ATOMIC_RELAXED);
+    pid_t p;
+    while ((p = wait(NULL)) == -1) {  }
+  } else {
+    // child
+    child();
+  }
+}
+
+int main() {
+  const int kChildren = 30;
+  for (int i = 0; i < kChildren; ++i) {
+    pid_t pid = fork();
+    if (pid) {
+      // parent
+    } else {
+      test();
+      exit(0);
+    }
+  }
+
+  for (int i = 0; i < kChildren; ++i) {
+    pid_t p;
+    while ((p = wait(NULL)) == -1) {  }
+  }
+
+  return 0;
+}
+
+// Expect 30 (== kChildren) "done" messages.
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done
+// CHECK: done