more info

[Robert W. Kerns <RWK at MIT-MC>]

    Date: 19 JAN 1980 0255-EST
    From: RLB at MIT-MC (Richard L. Bryan)
    To:   (BUG DDT)
    Re:   more info

    Start a Lisp without symbols in DDT.
    (SETQ SYMBOLS T)
    Load HUMBLE from LISP;.
    See DDT BUG DO :BUG DDT ...

    The Lisp is doing
    	.BREAK 12,[..SSTB,,T] with T/ -302,,mumble
    at LDPUTM+6.

    Thereafter, at strange times, having to do with job manipulation, the bug
    msg reappears.  I encountered occurrences of jobs doing .BREAK 12, at startup.
    If such jobs are reselected, the BUG DDT ... happens again. 

    :SELF
    :PDUMP MC:CRASH;RLB .BREAK

The :SELF is unecessary.  Undesirable even.

I think LISP is passing up a malformed symbol table, fucking DDT over
royally.  As near as I can tell from the totally inadaquate
documentation on this feature, LISP should be passing a symbol table,
as documented in DDT ORDER.  It's not easy for DDT to protect itself
from this kind of lossage.

As I understand it, this is what you should be doing.  It seems to work
ok for me.

1)  Turn on %SYGBL in the symbols.  Either that or %SYLCL *MUST* be
set, as documented in DDT ORDER.
2)  By the way, I assume it's LISP that's clearing out the %SYHKL bit
in the symbols being passed up.  Please make it stop doing that, It
makes the SYMBOLS T feature completely useless since it hides important
symbols like A.
3)  Put all the symbols in a symbol block.  I'd suggest, for maximum
utility, putting them into a block named after the FN1 of the FASL
file.

I.e.
SYMS:	.SQUOZE 0,TEST		   ;Test BLOCK
	-10,,1			   ;10 long, including 2 for header, level 1
	.SQUOZE %SYLCL,A
	1
	.SQUOZE %SYLCL,B
	2
	.SQUOZE %SYLCL,C
	3

GO:	.BREAK 12,[..SSTB,,[-10,,SYMS]]