1
2
3
4
5
6
7
8
9
10
11
12
|
<h1 class="section">Suppressing Inheritance</h1> <p>As described in previous sections, <code>make</code> variables are inherited by prerequisites. This capability allows you to modify the behavior of a prerequisite based on which targets caused it to be rebuilt. For example, you might set a target-specific variable on a <code>debug</code> target, then running ‘<samp>make debug</samp>’ will cause that variable to be inherited by all prerequisites of <code>debug</code>, while just running ‘<samp>make all</samp>’ (for example) would not have that assignment. </p> <p>Sometimes, however, you may not want a variable to be inherited. For these situations, <code>make</code> provides the <code>private</code> modifier. Although this modifier can be used with any variable assignment, it makes the most sense with target- and pattern-specific variables. Any variable marked <code>private</code> will be visible to its local target but will not be inherited by prerequisites of that target. A global variable marked <code>private</code> will be visible in the global scope but will not be inherited by any target, and hence will not be visible in any recipe. </p> <p>As an example, consider this makefile: </p>
<div class="example"> <pre class="example">EXTRA_CFLAGS =
prog: private EXTRA_CFLAGS = -L/usr/local/lib
prog: a.o b.o
</pre>
</div> <p>Due to the <code>private</code> modifier, <code>a.o</code> and <code>b.o</code> will not inherit the <code>EXTRA_CFLAGS</code> variable assignment from the <code>prog</code> target. </p><div class="_attribution">
<p class="_attribution-p">
Copyright © 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022 Free Software Foundation, Inc. <br>Licensed under the GNU Free Documentation License.<br>
<a href="https://www.gnu.org/software/make/manual/html_node/Suppressing-Inheritance.html" class="_attribution-link">https://www.gnu.org/software/make/manual/html_node/Suppressing-Inheritance.html</a>
</p>
</div>
|
