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+
+		 The Code Pedigree of This Directory
+
+
+This directory contains a big merge of several development lines of
+gas as well as a few bug fixes and some configuration that I've added
+in order to retain my own sanity.
+
+A little history.
+
+The only common baseline of all versions was gas-1.31.
+
+From 1.31, Intel branched off and added:
+
+	support for the Intel 80960 (i960) processor.
+	support for b.out object files.
+	some bug fixes.
+	sloppy mac MPW support
+	Intel gnu/960 makefiles and version numbering.
+
+Many of the bug fixes found their way into the main development line
+prior to 1.36.  ALL intel changes were ifdef'd I80960.  This was good
+as it isolated the changes, but bad in that it connected the b.out
+support to the i960 support, and bad in that the bug fixes were only
+active in the i960+b.out executables of gas, (although most of these
+were nicely marked with comments indicating that they were probably
+general bug fixes.)
+
+To pick up the main FSF development line again, along the way to 1.36,
+several new processors were added, many bugs fixed, and the world was
+a somewhat better place in general.
+
+From gas-1.36, Loic at Axis Design (france!) encapsulated object
+format specific actions, added coff versions of those encapsulations,
+and a config.gas style configuration and Makefile.  This was a big
+change and a lot of work.
+
+Then along came the FIRST FSF release of gas-1.37.  I say this because
+there have been at least two releases of gas-1.37.  Only two of them
+do we care about for this story, so let's call them gas-1.37.1 and
+gas-1.37.2.
+
+Here starts the confusion.  Firstly, gas-1.37.1 did not compile.
+
+In the meantime, John Gilmore at Cygnus Support had been hacking
+gas-1.37.1.  He got it to compile.  He added support for the AMD 29000
+processor.  AND he started encapsulating some of the a.out specific
+pieces of code mostly into functions.  AND he rebuilt the relocation
+info to be generic.  AND he restructured somewhat so that for a single
+host, cross assemblers could be built for all targets in the same
+directory.  Useful work but a considerable nuisance because the a29k
+changes were not partitioned from the encapsulation changes, the
+encapsulation changes were incomplete, and the encapsulation required
+functions where alternate structuring might have used macros. Let's
+call this version gas-1.37.1+a29k.
+
+By the time gas-1.37.2 was "released", (remember that it TOO was
+labelled by FSF as gas-1.37), it compiled, but it also added i860
+support and ansi style const declarations.
+
+At this point, Loic rolled his changes into gas-1.37.2.
+
+What I've done.
+
+I collected all the stray versions of gas that sounded relevant to my
+goals of cross assembly and alternate object file formats and the FSF
+releases from which the stray versions had branched.
+
+I rolled the Intel i960 changes from 1.31 into versions that I call
+1.34+i960, 1.36+i960, and then 1.37.1+i960.
+
+Then I merged 1.37.1+i960 with 1.37.1+a29k to produce what I call
+1.37.1+i960+a29k or 1.37.3.
+
+From 1.37.3, I pulled in Loic's stuff.  This wasn't easy as Loic's
+stuff hit all the same points as John's encapsulations.  Loic's goal
+was to split the a.out from coff dependancies for native assembly on
+coff, while John's was to split for multiple cross assembly from a
+single host.
+
+Loic's config arranged files much like emacs into m-*, etc.  I've
+rearranged these somewhat.
+
+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.
+
+
+-----
+
+reloc now stored internally as generic. (symbols too?) (segment types
+vs. names?)
+
+I don't mean to overlook anyone here.  There have also been several
+other development lines here that I looked at and elected to bypass.
+Specifically, xxx's stabs in coff stuff was particularly tempting.