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+
+		      The GAS Configuration Plan
+
+Theory:
+
+The goal of the new configuration scheme is to bury all object format,
+target processor, and host machine dependancies in object, target, and
+host specific files.  That is, to move all #ifdef's out of the gas
+common code.
+
+Here's how it works.  There is a .h and a .c file for each object file
+format, a .h and a .c file for each target processor, and a .h for
+each host.  config.gas creates {sym}links in the current directory to
+the appropriate files in the config directory.  config.gas also serves
+as a list of triplets {host, target, object-format} that have been
+tested at one time or another.  I also recommend that config.gas be
+used to document triplet specific notes as to purpose of the triplet,
+etc.
+
+Implementation:
+
+host.h is a {sym}link to .../config/xm-yourhost.h.  It is intended to
+be used to hide host compiler, system header file, and system library
+differences between host machines.  If your host needs actual c source
+files, then either: these are generally useful functions, in which
+case you should probably build a local library outside of the gas
+source tree, or someone, perhaps me, is confused about what is needed
+by different hosts.
+
+obj-format.h is a {sym}link to .../config/obj-something.h.  It is intended
+
+All gas .c files include as.h.
+
+as.h #define's "gas", includes host.h, defines a number of gas
+specific structures and types, and then includes tp.h, obj.h, and
+target-environment.h.
+
+target-environment.h defines a target environment specific
+preprocessor flag, eg, TE_SUN, and then includes obj-format.h.
+
+obj-format.h defines an object format specific preprocessor flag, eg,
+OBJ_AOUT, OBJ_BOUT, OBJ_COFF, includes "target-processor.h", and then
+defines the object specific macros, functions, types, and structures.
+
+target-processor.h 
+
+target-processor.
+
+Porting:
+
+There appear to be four major types of ports; new hosts, new target
+processors, new object file formats, and new target environments.