Do not rely on uniquiness of pthread_t

src/platform-cygwin.cc

Index: src/platform-cygwin.cc
diff --git a/src/platform-cygwin.cc b/src/platform-cygwin.cc
index d591b9dc27162e5432dc29d6a59f260769aaf7d5..65113282be38788799aa173c2003bb4a968d781b 100644
--- a/src/platform-cygwin.cc
+++ b/src/platform-cygwin.cc
@@ -362,50 +362,17 @@ bool VirtualMemory::Uncommit(void* address, size_t size) {
 }
 
 
-class ThreadHandle::PlatformData : public Malloced {
+class Thread::PlatformData : public Malloced {
  public:
-  explicit PlatformData(ThreadHandle::Kind kind) {
-    Initialize(kind);
-  }
-
-  void Initialize(ThreadHandle::Kind kind) {
-    switch (kind) {
-      case ThreadHandle::SELF: thread_ = pthread_self(); break;
-      case ThreadHandle::INVALID: thread_ = kNoThread; break;
-    }
-  }
-
+  PlatformData() : thread_(kNoThread) {}
   pthread_t thread_;  // Thread handle for pthread.
 };
 
 
-ThreadHandle::ThreadHandle(Kind kind) {
-  data_ = new PlatformData(kind);
-}
-
-
-void ThreadHandle::Initialize(ThreadHandle::Kind kind) {
-  data_->Initialize(kind);
-}
-
-
-ThreadHandle::~ThreadHandle() {
-  delete data_;
-}
-
-
-bool ThreadHandle::IsSelf() const {
-  return pthread_equal(data_->thread_, pthread_self());
-}
-
-
-bool ThreadHandle::IsValid() const {
-  return data_->thread_ != kNoThread;
-}
 
 
 Thread::Thread(Isolate* isolate, const Options& options)
-    : ThreadHandle(ThreadHandle::INVALID),
+    : data_(new PlatformData),
       isolate_(isolate),
       stack_size_(options.stack_size) {
   set_name(options.name);
@@ -413,7 +380,7 @@ Thread::Thread(Isolate* isolate, const Options& options)
 
 
 Thread::Thread(Isolate* isolate, const char* name)
-    : ThreadHandle(ThreadHandle::INVALID),
+    : data_(new PlatformData),
       isolate_(isolate),
       stack_size_(0) {
   set_name(name);
@@ -421,6 +388,7 @@ Thread::Thread(Isolate* isolate, const char* name)
 
 
 Thread::~Thread() {
+  delete data_;
 }
 
 
@@ -429,8 +397,8 @@ static void* ThreadEntry(void* arg) {
   // This is also initialized by the first argument to pthread_create() but we
   // don't know which thread will run first (the original thread or the new
   // one) so we initialize it here too.
-  thread->thread_handle_data()->thread_ = pthread_self();
-  ASSERT(thread->IsValid());
+  thread->data()->thread_ = pthread_self();
+  ASSERT(thread->data()->thread_ != kNoThread);
   Thread::SetThreadLocal(Isolate::isolate_key(), thread->isolate());
   thread->Run();
   return NULL;
@@ -451,13 +419,13 @@ void Thread::Start() {
     pthread_attr_setstacksize(&attr, static_cast<size_t>(stack_size_));
     attr_ptr = &attr;
   }
-  pthread_create(&thread_handle_data()->thread_, attr_ptr, ThreadEntry, this);
-  ASSERT(IsValid());
+  pthread_create(&data_->thread_, attr_ptr, ThreadEntry, this);
+  ASSERT(data_->thread_ != kNoThread);
 }
 
 
 void Thread::Join() {
-  pthread_join(thread_handle_data()->thread_, NULL);
+  pthread_join(data_->thread_, NULL);
 }