+#include "llvm/Config/config.h"
+#include "llvm/Support/Mutex.h"
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only TRULY operating system
+//=== independent code.
+//===----------------------------------------------------------------------===//
+
+#if !defined(LLVM_ENABLE_THREADS) || LLVM_ENABLE_THREADS == 0
+// Define all methods as no-ops if threading is explicitly disabled
+namespace llvm {
+using namespace sys;
+MutexImpl::MutexImpl( bool recursive) { }
+MutexImpl::~MutexImpl() { }
+bool MutexImpl::acquire() { return true; }
+bool MutexImpl::release() { return true; }
+bool MutexImpl::tryacquire() { return true; }
+}
+#else
+
+#if defined(HAVE_PTHREAD_H) && defined(HAVE_PTHREAD_MUTEX_LOCK)
+
+#include <cassert>
+#include <pthread.h>
+#include <stdlib.h>
+
+namespace llvm {
+using namespace sys;
+
+// Construct a Mutex using pthread calls
+MutexImpl::MutexImpl( bool recursive)
+ : data_(0)
+{
+ // Declare the pthread_mutex data structures
+ pthread_mutex_t* mutex =
+ static_cast<pthread_mutex_t*>(malloc(sizeof(pthread_mutex_t)));
+ pthread_mutexattr_t attr;
+
+ // Initialize the mutex attributes
+ int errorcode = pthread_mutexattr_init(&attr);
+ assert(errorcode == 0); (void)errorcode;
+
+ // Initialize the mutex as a recursive mutex, if requested, or normal
+ // otherwise.
+ int kind = ( recursive ? PTHREAD_MUTEX_RECURSIVE : PTHREAD_MUTEX_NORMAL );
+ errorcode = pthread_mutexattr_settype(&attr, kind);
+ assert(errorcode == 0);
+
+#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) && \
+ !defined(__DragonFly__) && !defined(__Bitrig__)
+ // Make it a process local mutex
+ errorcode = pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_PRIVATE);
+ assert(errorcode == 0);
+#endif
+
+ // Initialize the mutex
+ errorcode = pthread_mutex_init(mutex, &attr);
+ assert(errorcode == 0);