[Simh] pdp7/decsys/fortran, a different bug

[Christopher Osburn]

Salutations!

Those who are having trouble with the floating point in the DECsys  
FORTRAN compiler are head and shoulders ahead of me.  Currently all I  
have is continual looping of the message "ILF01 0".  No invalid  
instructions, tried that.  Let it run for an hour, just for fun.  It  
kept doing the same thing just for fun.

The compiler *is* trying.  When I introduce a syntax error to my  
source, I get a slightly different message.  So, we'll assume  
operator error, since the operator is (usually) the easiest thing to  
fix...

My setup:

PDP-7 simulator V3.7-2 [32b data, 32b addresses, no Ethernet]
(compiled on:  Darwin bolt.mraiow.com 8.10.0 Darwin Kernel Version  
8.10.0: Wed May 23 16:50:59 PDT 2007; root:xnu-792.21.3~1/RELEASE_PPC  
Power Macintosh powerpc) (aka MacOS 10.4.10)
(compiled with:  powerpc-apple-darwin8-gcc-4.0.1 (GCC) 4.0.1 (Apple  
Computer, Inc. build 5250))

decsys.ini:
att dt2 decsys.dtp
att dt3 scratch.dtp
load decsys.rim 17640

(decsys.dtp and decsys.rim from the distribution, scratch.dtp empty)

The session:

$ pdp7 decsys.ini
sim> run

GA
EDIT!
READY TAPES ON TWO AND THREE
Z
F,TEST!


TEXT MODE
       PROGRAM TEST		(let's keep it simple)
       END

<DEL>
END TEXT MODE

OK

<DEL>
READY TAPES ON TWO AND THREE
K
GA
CONTEN!
INDICATE REQUIRED FILES (S,L,W)
W!
CAB DECSYS7 COPY   15 JUNE 1966
TEST W 0143,0000,0000
GA
COMPIL!
ENABLE WRITE ON TWO,THREE
USE W(AIT) OR G(O)
W,TEST!				(WAIT or GO, same result)
ILF01  0

ILF01  0

ILF01  0

ILF01  0

^E				(that's enough...)
Simulation stopped, PC: 10617 (JMP 10616)
sim> q
$

I just refreshed my copy of the kit from the website, same result.

Has anyone else seen this?  Anyone have a clue-by-four they can whack  
me with? :-)

Thanks in advance
Chris
kd7dvd [whirlpool] gmail [spot] com