File: make.info,  Node: Variables in Recipes,  Prev: Splitting Recipe Lines,  Up: Recipe Syntax

5.1.2 Using Variables in Recipes
--------------------------------

The other way in which 'make' processes recipes is by expanding any
variable references in them (*note Basics of Variable References:
Reference.).  This occurs after make has finished reading all the
makefiles and the target is determined to be out of date; so, the
recipes for targets which are not rebuilt are never expanded.

   Variable and function references in recipes have identical syntax and
semantics to references elsewhere in the makefile.  They also have the
same quoting rules: if you want a dollar sign to appear in your recipe,
you must double it ('$$').  For shells like the default shell, that use
dollar signs to introduce variables, it's important to keep clear in
your mind whether the variable you want to reference is a 'make'
variable (use a single dollar sign) or a shell variable (use two dollar
signs).  For example:

     LIST = one two three
     all:
             for i in $(LIST); do \
                 echo $$i; \
             done

results in the following command being passed to the shell:

     for i in one two three; do \
         echo $i; \
     done

which generates the expected result:

     one
     two
     three