Copyright 2013 -> 2014

[folly.git] / folly / Portability.h

diff --git a/folly/Portability.h b/folly/Portability.h
index 1095164f4474a85c7624b348f00d0ce1145e0900..b227ba0da9ecf2f9018b7481bb67f870ab584c9a 100644 (file)
--- a/folly/Portability.h
+++ b/folly/Portability.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013 Facebook, Inc.
+ * Copyright 2014 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,6 +25,7 @@
 #include <features.h>
 #endif
 
+#include "CPortability.h"
 
 #if FOLLY_HAVE_SCHED_H
  #include <sched.h>
@@ -84,38 +85,49 @@ struct MaxAlign { char c; } __attribute__((aligned));
 # endif
 #endif
 
+// It turns out that GNU libstdc++ and LLVM libc++ differ on how they implement
+// the 'std' namespace; the latter uses inline namepsaces. Wrap this decision
+// up in a macro to make forward-declarations easier.
+#if FOLLY_USE_LIBCPP
+#define FOLLY_NAMESPACE_STD_BEGIN     _LIBCPP_BEGIN_NAMESPACE_STD
+#define FOLLY_NAMESPACE_STD_END       _LIBCPP_END_NAMESPACE_STD
+#else
+#define FOLLY_NAMESPACE_STD_BEGIN     namespace std {
+#define FOLLY_NAMESPACE_STD_END       }
+#endif
 
-/* Define a convenience macro to test when address sanitizer is being used
- * across the different compilers (e.g. clang, gcc) */
-#if defined(__clang__)
-# if __has_feature(address_sanitizer)
-#  define FOLLY_SANITIZE_ADDRESS 1
-# endif
-#elif defined (__GNUC__) && \
-      (((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ >= 5)) && \
-      __SANITIZE_ADDRESS__
-# define FOLLY_SANITIZE_ADDRESS 1
+// Some platforms lack clock_gettime(2) and clock_getres(2). Inject our own
+// versions of these into the global namespace.
+#if FOLLY_HAVE_CLOCK_GETTIME
+#include <time.h>
+#else
+#include "folly/detail/Clock.h"
 #endif
 
-/* Define attribute wrapper for function attribute used to disable
- * address sanitizer instrumentation. Unfortunately, this attribute
- * has issues when inlining is used, so disable that as well. */
-#ifdef FOLLY_SANITIZE_ADDRESS
-# if defined(__clang__)
-#  if __has_attribute(__no_address_safety_analysis__)
-#   define FOLLY_DISABLE_ADDRESS_SANITIZER \
-      __attribute__((__no_address_safety_analysis__, __noinline__))
-#  elif __has_attribute(__no_sanitize_address__)
-#   define FOLLY_DISABLE_ADDRESS_SANITIZER \
-      __attribute__((__no_sanitize_address__, __noinline__))
-#  endif
-# elif defined(__GNUC__)
-#  define FOLLY_DISABLE_ADDRESS_SANITIZER \
-     __attribute__((__no_address_safety_analysis__, __noinline__))
-# endif
+// Provide our own std::__throw_* wrappers for platforms that don't have them
+#if FOLLY_HAVE_BITS_FUNCTEXCEPT_H
+#include <bits/functexcept.h>
+#else
+#include "folly/detail/FunctionalExcept.h"
 #endif
-#ifndef FOLLY_DISABLE_ADDRESS_SANITIZER
-# define FOLLY_DISABLE_ADDRESS_SANITIZER
+
+#if defined(__cplusplus)
+// Unfortunately, boost::has_trivial_copy<T> is broken in libc++ due to its
+// usage of __has_trivial_copy(), so we can't use it as a
+// least-common-denominator for C++11 implementations that don't support
+// std::is_trivially_copyable<T>.
+//
+//      http://stackoverflow.com/questions/12754886/has-trivial-copy-behaves-differently-in-clang-and-gcc-whos-right
+//
+// As a result, use std::is_trivially_copyable() where it exists, and fall back
+// to Boost otherwise.
+#if FOLLY_HAVE_STD__IS_TRIVIALLY_COPYABLE
+#include <type_traits>
+#define FOLLY_IS_TRIVIALLY_COPYABLE(T)      (std::is_trivially_copyable<T>::value)
+#else
+#include <boost/type_traits.hpp>
+#define FOLLY_IS_TRIVIALLY_COPYABLE(T)      (boost::has_trivial_copy<T>::value)
 #endif
+#endif // __cplusplus
 
 #endif // FOLLY_PORTABILITY_H_