-for example a working C compiler, make tool, GNU automake and autoconf (only
-when not using a distribution archive), and a few libraries depending on the
-features you want to compile in (like IDENT support, SSL, and PAM).
+for example a working C compiler, make tool, and a few libraries depending on
+the feature set you want to enable at compile time (like IDENT, SSL, and PAM).
+
+And if you aren't using a distribution archive ("tar.gz" file), but cloned the
+plain source archive, you need a few additional tools to generate the build
+system itself: GNU automake and autoconf, as well as pkg-config.