如何在makefile中定义一个变量，然后在Fortran代码中使用它 [英] How to define a variable in a makefile and then use it within Fortran code

问题描述

我试图在makefile中定义一个变量，然后根据是否设置该变量，更改在我的Fortran例程中编译哪个代码块。

I am trying to define a variable in a makefile, and then depending on whether that variable is set, change which code block is compiled in my Fortran routine.

简单的例子我不能工作：

Simple example I can't get working:

program test
    implicit none
    integer :: a
#ifdef MYVAR
    a = 1
#else
    a = 0
#endif
    write(*,*) a
end program test

我的makefile是：

My makefile is:

MYVAR=1
all:
    ifort temp.F90 -fpp
    echo $(MYVAR)

echo $（MYVAR）行可以正确打印1.但是，当测试程序编译时，它设置a = 0。如何获得Fortran代码来识别MYVAR？

The echo $(MYVAR) line correctly prints 1. However, when the test program is compiled it sets a=0. How do I get the Fortran code to recognize MYVAR?

推荐答案

您需要添加一个额外的标志

You need to add an extra flag

OPTIONS = -DMYVAR=$(MYVAR)

，然后用

and then you compile it with

all:
    ifort $(OPTIONS) <file.f90> -fpp

你应该很好去。

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