在Makefile中设置编译器名称

Question

I have a Makefile suppose to compile my app in multiple host, some of them has built in intel compiler (icpc) and others just have g++. I would like that makefile automatically detect availability of icpc and if it is available, compile application with intel compiler, otherwise just compile it with g++.

How do I have to change Makefile to automatically detect availability of icpc compiler ?

Here is my try which simply did not work

ERR = $(shell icpc 2>/dev/null ; echo $? )
ifeq "$(ERR)" "127"
    CXX = g++
else
    CXX = icpc
endif

Answer 1

You can use which for detecting icpc instead. Also better check against 0 instead of 127 , since there may be differences from one system to another

ERR = $(shell which icpc >/dev/null; echo $$?)
ifeq "$(ERR)" "0"
    CXX = icpc
else
    CXX = g++
endif

all:
    echo $(CXX)