environment variable, like optimization, debugging information and
warning levels. If omitted, it defaults to @option{-g
-O2}.@footnote{The @command{configure} script is itself generated from
-the file @file{configure.in}. It is only distributed in packaged
+the file @file{configure.ac}. It is only distributed in packaged
releases of GiNaC. If you got the naked sources, e.g. from CVS, you
must generate @command{configure} along with the various
-@file{Makefile.in} by using the @command{autogen.sh} script.}
+@file{Makefile.in} by using the @command{autogen.sh} script. This will
+require a fair amount of support from your local toolchain, though.}
The whole process is illustrated in the following two
examples. (Substitute @command{setenv @var{VARIABLE} @var{value}} for