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//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. Note that for the moment, as long as building gate using gcc 4.4.4 as the primary compiler is supported, libast/i386/FEATURE/aso has some additional local edits to use the appropriate atomic ops for 32-bit objects built with this version of gcc.