This port engages in a long, computationally-demanding tuning process.
	Builds can take a day or more on older hardware, and can temporarily
	occupy several hundred megabytes of disk space.  You are advised to
	disable all forms of power management or CPU throttling during the
	build, and to set operating parameters to static values at which you
	ultimately intend to use the software.  You should also avoid placing
	heavy loads on the system during the build, and temporarily disable
	any automatons that may do so.  If you fail to follow these guidelines,
	you may prolong the build and obtain libraries with sub-optimal
	performance.

	Occasionally the auto-configuration may fail for certain platforms,
	and you may have to override the architecture, compiler flags, assembly
	language dialect, or pointer bit-width by issuing additional configure
	arguments.  Consult the FAQ, installation guide, and errata page at
	the project website for help if this is necessary, and notify the
	port maintainer.  Note that in most cases the port intentionally
	overrides user-selected compiler flags.

	If your machine will be solely dedicated to building atlas during the
	lengthy optimization process, and not subjected to other loads, you
	may enable the more accurate wall timer (instead of the default
	CPU-time timer) with the WALL_TIMER option.

	If you want to override the architecture auto-detection, and use a
	specific architectural default, then set WITH_ARCHDEF and define
	ARCHDEF to be either the full path to a gzipped architectural default
	tarball with suffix .tgz, or the basename of such a tarball in the
	distribution CONFIG/ARCHS sub-directory.  If you want to ignore all
	architectural defaults, set WITH_ARCHDEF and define ARCHDEF=NONE.
	Note that the use of versioned compiler names in Ports may prevent
	the use of architectural default tarballs constructed on other systems
	without some changes to their directory structure.