guy@rlgvax.UUCP (Guy Harris) (08/06/83)
The following was originally posted by: Dale Mosby, Rand Dow: rand.orstcs@RAND-RELAY as a bug in 2.8BSD, but the bug comes from V7 (and has been fixed in System III). When the stack is expanded, routine `backup' (file mch.s) is executed to take care of instruction restart. A flag called `fflg' is incremented when the instruction is a floating point instruction. Unfortunately this flag is NEVER cleared so subsequent stack expands may not be executed correctly. This remains like that until the system is rebooted. The single instruction fix follows: file mch.s (or mch.c) . . /* hard part * simulate the ssr2 register missing on 11/40 */ backup: clr r2 / backup register ssr1 mov $1,bflg / clrs jflg clrb fflg / INSERTED INSTRUCTION **** mov ssr+4,r0 jsr pc,fetch . .