1.2.5: will be tagged as "sbcl-1.2.5"
Remove dead variable
Fix overly conservative behavior of update_page_write_prot().

When scanning for old->young pointers, ignore immediate values
that might happen to return a valid result from find_page_index().
At worst, this caused pages to fail to be protected when they could
have been, so it was not damaging, only suboptimal.
fix Huffman table build non-determinism

when building, there might be symbols in the symbol code with
the same implied probability (case in point, the #\( and #\)
characters).  We must make sure that those are processed in
the same order no matter the host's hash-table implementation,
so insert enough SORT / STABLE-SORTs to make that happen.

The hash-table manipulations around the Huffman database in
src/code/target-char.lisp do not lead to any non-determinism:
the outputs eventually get sorted by guaranteed-unique keys
(the character code, or the character name's encoding relative
to the now-deterministic Huffman table).
Remove unnecessary code from CIRCLE-SUBST introduced in 88dab5bc.

The fix that avoided reading read raw slots with %INSTANCE-REF
also "fixed" the code to look for (impossible) circularities in such slots.
Replace a bunch of FIXMEs with a couple KLUDGEs.

This change gets rid of all symbols in SB-KERNEL that pertain to 64-bit
functions in a 32-bit target by altering the hack in Genesis that assumes
that for a subset of packages, all symbols present at dump time must
be interned in the cold core regardless of whether the symbol was observed
during loading of cold fasls.  Removing SB!KERNEL from the list of magic
packages reverts to the desirable behavior of interning only as needed.

Doing this exposed an interesting aspect of the DEFERR macro:
its expansion never mentions the symbol being defined, and use of that
symbol by way of GENERATE-ERROR-CODE also never mentions it.
To avoid disappearing error symbols, DEFERR now contains a counter-hack.
Nonetheless I think this is an improvement, as it avoids polluting
package-data-list with reader conditionals or somesuch.

There are some issues in SB!C still. Additionally, this exposed the fact
that TWO-ARG-{/=,<=,>=} were not supposed to be present in x86 targets.
LOOP: supply a better type for default init values.

When the default value is a vector it lets the length slip in,
proving difficult to optimize the types later.

Fixes lp#1388150.
Add VIM tempfiles to ignore list.
Make TN-ID (and therefore all VOP-print-functions) work everywhere.

Previously they'd stumble upon unbound variables if called outside
of WITH-COMPILATION-VALUES.
Keep the package away from the TN printed representation.
New macro DO-IR2-BLOCKS-REVERSE.
Capture a VOP tree for analyzing.
If set during SBCL compilation, dump the VOP tree to a text file.
Replacing a common sequence with an unconditional jump. TODO
Some snippets for testing.