This area contains the build configuration for selected AT&T Software Technology
(AST) libraries and commands. In particular ksh (the illumos /bin/sh), its
supporting libraries and and a small number of system commands, see
./ksh/builtins/alias.c

The source for these components is in usr/src/contrib/ast/; see the README
file there for more information.

The AST library builds use FEATURE files to describe the capabilities of the
host system and build environment (similar to the output from tools like
GNU autoconf). In order to support cross compilation and ensure reproducible
builds, these files are present in this tree under libXXX/<arch>/FEATURE/
alongside a small number of other generated files.

The FEATURE files can be re-generated based on the current contents of
proto using 'make _feature' in this directory. This should be done after
adding new features to the standard libraries that AST can detect and use.
This needs to be done for all supported architectures.