unittests/SupportTests/Initialize.MultipleThreads: Appease --vg-leak …

…to allocate stack explicitly for glibc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173350 91177308-0d34-0410-b5e6-96231b3b80d8

unittests/Support/ManagedStatic.cpp

@@ -26,17 +26,32 @@ namespace test1 {
     *ms;
     return NULL;
   }
+
+  // Valgrind's leak checker complains glibc's stack allocation.
+  // To appease valgrind, we provide our own stack for each thread.
+  void *allocate_stack(pthread_attr_t &a, size_t n = 65536) {
+    void *stack = malloc(n);
+    pthread_attr_init(&a);
+    pthread_attr_setstack(&a, stack, n);
+    return stack;
+  }
 }
 
 TEST(Initialize, MultipleThreads) {
   // Run this test under tsan: http://code.google.com/p/data-race-test/
 
+  pthread_attr_t a1, a2;
+  void *p1 = test1::allocate_stack(a1);
+  void *p2 = test1::allocate_stack(a2);
+
   llvm_start_multithreaded();
   pthread_t t1, t2;
-  pthread_create(&t1, NULL, test1::helper, NULL);
-  pthread_create(&t2, NULL, test1::helper, NULL);
+  pthread_create(&t1, &a1, test1::helper, NULL);
+  pthread_create(&t2, &a2, test1::helper, NULL);
   pthread_join(t1, NULL);
   pthread_join(t2, NULL);
+  free(p1);
+  free(p2);
   llvm_stop_multithreaded();
 }
 #endif