Not define thread_local for scenarios with c++11 off

src/butil/thread_local.h

@@ -25,22 +25,6 @@
 #include <cstddef>                  // NULL
 #include "butil/macros.h"            
 
-// Provide thread_local keyword (for primitive types) before C++11
-// DEPRECATED: define this keyword before C++11 might make the variable ABI
-// incompatible between C++11 and C++03
-#if !defined(thread_local) &&                                           \
-    (__cplusplus < 201103L ||                                           \
-     (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) < 40800)
-// GCC supports thread_local keyword of C++11 since 4.8.0
-#ifdef _MSC_VER
-// WARNING: don't use this macro in C++03
-#define thread_local __declspec(thread)
-#else
-// WARNING: don't use this macro in C++03
-#define thread_local __thread
-#endif  // _MSC_VER
-#endif
-
 #ifdef _MSC_VER
 #define BAIDU_THREAD_LOCAL __declspec(thread)
 #else
@@ -58,9 +42,8 @@ template <typename T> inline T* get_thread_local();
 // thread, fn will be called at program termination. Calling sequence is LIFO:
 // last registered function will be called first. Duplication of functions 
 // are not checked. This function is often used for releasing thread-local
-// resources declared with __thread (or thread_local defined in 
-// butil/thread_local.h) which is much faster than pthread_getspecific or
-// boost::thread_specific_ptr.
+// resources declared with __thread which is much faster than
+// pthread_getspecific or boost::thread_specific_ptr.
 // Returns 0 on success, -1 otherwise and errno is set.
 int thread_atexit(void (*fn)());
 int thread_atexit(void (*fn)(void*), void* arg);