makefile tips

shell

#!/bin/sh -e

选项-e表示一个命令在执行后返回一个非0状态值时，就退出

$(@:_config=)：$@是make的自动变量，标识规则的目标名

if $@=smdk6410_config

$(@:_config=) then $@=smdk6410

 ${parameter%%word}
              Remove matching suffix pattern.  The word is expanded to produce
              a pattern just as in pathname expansion.  If the pattern matches
              a  trailing portion of the expanded value of parameter, then the
              result of the expansion is the expanded value of parameter  with
              the  shortest  matching  pattern (the ``%'' case) or the longest
              matching pattern (the ``%%'' case) deleted. 

If parameter  is  @ or  *,  the  pattern  removal operation is applied to each posi‐
              tional parameter in turn, and the  expansion  is  the  resultant
              list.  

If  parameter is an array variable subscripted with @ or  *, the pattern removal operation is applied to  each  member  of
              the array in turn, and the expansion is the resultant list.

makefile 变量

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