15. Obsolete Constructs

Autoconf changes, and throughout the years some constructs have been obsoleted. Most of the changes involve the macros, but in some cases the tools themselves, or even some concepts, are now considered obsolete.

You may completely skip this chapter if you are new to Autoconf. Its intention is mainly to help maintainers updating their packages by understanding how to move to more modern constructs.

15.1 Obsolete `config.status' Invocation		Different calling convention
15.2 `acconfig.h'		Additional entries in `config.h.in'
15.3 Using autoupdate to Modernize `configure.ac'		Automatic update of `configure.ac'
15.4 Obsolete Macros		Backward compatibility macros
15.5 Upgrading From Version 1		Tips for upgrading your files
15.6 Upgrading From Version 2.13		Some fresher tips