#! /bin/sh
#
# cpp11-clang
#
# Detect compatible Clang version and add c++11/14 flags
#

CXXMAJOR   := $(shell $(CXX) -x c++ /dev/null -dM -E | grep __clang_major__ | sed -e 's/^.* //g')
CXXMINOR   := $(shell $(CXX) -x c++ /dev/null -dM -E | grep __clang_minor__ | sed -e 's/^.* //g')
CXXPATCH   := $(shell $(CXX) -x c++ /dev/null -dM -E | grep __clang_patchlevel__ | sed -e 's/^.* //g')
CXXVERSION := $(CXXMAJOR)$(CXXMINOR)$(CXXPATCH)

#
# Clang 3.4 doesn't accept -std=c++14, only -std=c++1y.
#

# C++14 needs Clang 3.4
ifeq ($(shell test $(CXXVERSION) -ge 340 && echo 1), 1)
	CXXFLAGS += -std=c++1y
# C++11 needs Clang 3.3
else ifeq ($(shell test $(CXXVERSION) -ge 330 && echo 1), 1)
	CXXFLAGS += -std=c++0x
endif