+ `make doc' sends the output from most of the compilation to
+logfiles. If the build fails for any reason, it should prompt you with
+the name of a logfile which will provide information to help you work
+out why the build failed. These logfiles are not deleted with
+`make doc-clean'. To remove all the logfiles generated by the
+compilation process, use:
+
+ make log-clean
+
+ `make doc' compiles the documents for all languages. To save some
+compile time, the English language documents can be compiled on their
+own with:
+
+ make LANGS='' doc
+
+Similarly, it is possible to compile a subset of the translated
+documentation by specifying their language codes on the command line.
+For example, the French and German translations are compiled with:
+
+ make LANGS='de fr' doc
+
+Note that this will also compile the English version.
+