HDFS-14033. [libhdfs++] Disable libhdfs++ build on systems that do not support thread_local. Contributed by Anatoli Shein.

Author: sunilgovind

hadoop-hdfs-project/hadoop-hdfs-native-client/src/CMakeLists.txt

@@ -138,7 +138,27 @@ endif()
 
 add_subdirectory(main/native/libhdfs)
 add_subdirectory(main/native/libhdfs-tests)
-add_subdirectory(main/native/libhdfspp)
+
+# Temporary fix to disable Libhdfs++ build on older systems that do not support thread_local
+include(CheckCXXSourceCompiles)
+unset (THREAD_LOCAL_SUPPORTED CACHE)
+set (CMAKE_REQUIRED_DEFINITIONS "-std=c++11")
+set (CMAKE_REQUIRED_LIBRARIES ${CMAKE_THREAD_LIBS_INIT})
+check_cxx_source_compiles(
+    "#include <thread>
+    int main(void) {
+      thread_local int s;
+      return 0;
+    }"
+    THREAD_LOCAL_SUPPORTED)
+if (THREAD_LOCAL_SUPPORTED)
+    add_subdirectory(main/native/libhdfspp)
+else()
+    message(WARNING
+    "WARNING: Libhdfs++ library was not built because the required feature thread_local storage \
+    is not supported by your compiler. Known compilers that support this feature: GCC 4.8+, Visual Studio 2015+, \
+    Clang (community version 3.3+), Clang (version for Xcode 8+ and iOS 9+).")
+endif (THREAD_LOCAL_SUPPORTED)
 
 if(REQUIRE_LIBWEBHDFS)
     add_subdirectory(contrib/libwebhdfs)

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/CMakeLists.txt

@@ -63,8 +63,8 @@ check_cxx_source_compiles(
 if (NOT THREAD_LOCAL_SUPPORTED)
   message(FATAL_ERROR
   "FATAL ERROR: The required feature thread_local storage is not supported by your compiler. \
-  Known compilers that support this feature: GCC, Visual Studio, Clang (community version), \
-  Clang (version for iOS 9 and later).")
+  Known compilers that support this feature: GCC 4.8+, Visual Studio 2015+, Clang (community \
+  version 3.3+), Clang (version for Xcode 8+ and iOS 9+).")
 endif (NOT THREAD_LOCAL_SUPPORTED)
 
 # Check if PROTOC library was compiled with the compatible compiler by trying