[cfe-commits] [libcxx] r159901 - /libcxx/trunk/include/__mutex_base

[Howard Hinnant]

Author: hhinnant
Date: Sat Jul  7 15:01:52 2012
New Revision: 159901

URL: http://llvm.org/viewvc/llvm-project?rev=159901&view=rev
Log:
Apply constexpr to the mutex constructor.  As a conforming extension, apply constexpr to the condition_variable constructor.  These are important because it enables the compiler to construct these types at compile time, even though the object will be non-const.  Since they are constructed at compile time, there is no chance of a data race before they are constructed.

Modified:
    libcxx/trunk/include/__mutex_base

Modified: libcxx/trunk/include/__mutex_base
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/__mutex_base?rev=159901&r1=159900&r2=159901&view=diff
==============================================================================
--- libcxx/trunk/include/__mutex_base (original)
+++ libcxx/trunk/include/__mutex_base Sat Jul  7 15:01:52 2012
@@ -38,7 +38,11 @@
 
 public:
     _LIBCPP_INLINE_VISIBILITY
+#ifndef _LIBCPP_HAS_NO_CONSTEXPR
+     constexpr mutex() : __m_ PTHREAD_MUTEX_INITIALIZER {}
+#else
      mutex() {__m_ = (pthread_mutex_t)PTHREAD_MUTEX_INITIALIZER;}
+#endif
      ~mutex();
 
 private:
@@ -297,7 +301,11 @@
     pthread_cond_t __cv_;
 public:
     _LIBCPP_INLINE_VISIBILITY
+#ifndef _LIBCPP_HAS_NO_CONSTEXPR
+    constexpr condition_variable() : __cv_ PTHREAD_COND_INITIALIZER {}
+#else
     condition_variable() {__cv_ = (pthread_cond_t)PTHREAD_COND_INITIALIZER;}
+#endif
     ~condition_variable();
 
 private: