Add the preconditions target per suggestion by Henrik Bach.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17373 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/MakefileGuide.html b/docs/MakefileGuide.html
index 6713db6..c73059b 100644
--- a/docs/MakefileGuide.html
+++ b/docs/MakefileGuide.html
@@ -44,6 +44,7 @@
<li><a href="#dist-check">dist-check</a></li>
<li><a href="#dist-clean">dist-clean</a></li>
<li><a href="#install">install</a></li>
+ <li><a href="#preconditions">preconditions</a></li>
<li><a href="#printvars">printvars</a></li>
<li><a href="#tags">tags</a></li>
<li><a href="#uninstall">uninstall</a></li>
@@ -308,6 +309,9 @@
<tr><td><a href="#install"><tt>install</tt></a></td><td>all</td>
<td>Copy built objects to installation directory.
</td></tr>
+ <tr><td><a href="#preconditions"><tt>preconditions</tt></a></td><td>all</td>
+ <td>Check to make sure configuration and makefiles are up to date.
+ </td></tr>
<tr><td><a href="#printvars"><tt>printvars</tt></a></td><td>all</td>
<td>Prints variables defined by the makefile system (for debugging).
</td></tr>
@@ -413,6 +417,17 @@
</div>
<!-- ======================================================================= -->
+<div class="doc_subsection"><a name="preconditions">preconditions</a></div>
+<div class="doc_text">
+ <p>This utility target checks to see if the <tt>Makefile</tt> in the object
+ directory is older than the <tt>Makefile</tt> in the source directory and
+ copies it if so. It also reruns the <tt>configure</tt> script if that needs to
+ be done and rebuilds the <tt>Makefile.config</tt> file similarly. Users may
+ overload this target to ensure that sanity checks are run <em>before</em> any
+ building of targets as all the targets depend on <tt>preconditions</tt>.</p>
+</div>
+
+<!-- ======================================================================= -->
<div class="doc_subsection"><a name="printvars">printvars</a></div>
<div class="doc_text">
<p>This utility target just causes LLVM to print out some of its variables so