Allow including LibCarla headers multiple times in UE4

LibCarla/source/compiler/disable-ue4-macros.h

@@ -5,20 +5,7 @@
 // For a copy, see <https://opensource.org/licenses/MIT>.
 
 #ifndef LIBCARLA_INCLUDED_DISABLE_UE4_MACROS_HEADER
-#  define LIBCARLA_INCLUDED_DISABLE_UE4_MACROS_HEADER
+#define LIBCARLA_INCLUDED_DISABLE_UE4_MACROS_HEADER
-#else
-#  error disable-ue4-macros.h should only be included once!
-#endif // LIBCARLA_INCLUDED_DISABLE_UE4_MACROS_HEADER
-
-#pragma push_macro("check")
-#undef check
-
-#if defined(__clang__)
-#  pragma clang diagnostic push
-#  pragma clang diagnostic ignored "-Wmissing-braces"
-#endif
-
-#define LIBCARLA_INCLUDED_FROM_UE4
 
 #ifndef BOOST_ERROR_CODE_HEADER_ONLY
 #  define BOOST_ERROR_CODE_HEADER_ONLY
@@ -35,6 +22,22 @@
 #  endif // __cpp_coroutines
 #endif // defined(__clang__)
 
+// NOTE(Andrei): disable warning generated by undefined macros
+// __GNUC__, __GNUC_MINOR__
+// MSGPACK_ARCH_AMD64
+// DBG, BETA, OFFICIAL_BUILD
+// NTDDI_WIN7SP1
+// _APISET_RTLSUPPORT_VER
+// _APISET_INTERLOCKED_VER
+// _APISET_SECURITYBASE_VER
+// _WIN32_WINNT_WINTHRESHOLD
+// NOTE(Andrei): Macros to detect which compiler is
+// http://nadeausoftware.com/articles/2012/10/c_c_tip_how_detect_compiler_name_and_version_using_compiler_predefined_macros
+#if defined(_MSC_VER)
+#  pragma warning(push)
+#  pragma warning(disable: 4668 4191)
+#endif
+
 namespace boost {
 
   static inline void throw_exception(const std::exception &e) {
@@ -43,5 +46,17 @@ namespace boost {
 
 } // namespace boost
 
+#endif // LIBCARLA_INCLUDED_DISABLE_UE4_MACROS_HEADER
+
+#define LIBCARLA_INCLUDED_FROM_UE4
+
+#if defined(__clang__)
+#  pragma clang diagnostic push
+#  pragma clang diagnostic ignored "-Wmissing-braces"
+#endif
+
 #pragma push_macro("TEXT")
 #undef TEXT
+
+#pragma push_macro("check")
+#undef check

LibCarla/source/compiler/enable-ue4-macros.h

@@ -7,6 +7,10 @@
 #pragma pop_macro("check")
 #pragma pop_macro("TEXT")
 
+#if defined(_MSC_VER)
+#  pragma warning(pop)
+#endif
+
 #if defined(__clang__)
 #  pragma clang diagnostic pop
 #endif

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Server/TheNewCarlaServer.cpp

@@ -11,23 +11,6 @@
 
 #include "GameFramework/SpectatorPawn.h"
 
-// NOTE(Andrei): disable warning generated by undefined macros
-// __GNUC__, __GNUC_MINOR__
-// MSGPACK_ARCH_AMD64
-// DBG, BETA, OFFICIAL_BUILD
-// NTDDI_WIN7SP1
-// _APISET_RTLSUPPORT_VER
-// _APISET_INTERLOCKED_VER
-// _APISET_SECURITYBASE_VER
-// _WIN32_WINNT_WINTHRESHOLD
-
-// NOTE(Andrei): Macros to detect which compiler is
-//http://nadeausoftware.com/articles/2012/10/c_c_tip_how_detect_compiler_name_and_version_using_compiler_predefined_macros
-#if defined(_MSC_VER)
-  #pragma warning(push)
-  #pragma warning(disable: 4668 4191)
-#endif
-
 #include <compiler/disable-ue4-macros.h>
 #include <carla/Version.h>
 #include <carla/rpc/Actor.h>
@@ -39,9 +22,6 @@
 #include <carla/streaming/Server.h>
 #include <compiler/enable-ue4-macros.h>
 
-#if defined(_MSC_VER)
-  #pragma warning(pop)
-#endif
 #include <vector>
 
 // =============================================================================