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Posting-Version: version B 2.10.2 (Tek) 9/28/84 based on 9/17/84; site motel6.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!bellcore!decvax!decwrl!pyramid!hplabs!tektronix!reed!motel6!keith
From: keith@motel6.UUCP (Keith Packard)
Newsgroups: net.sources.bugs
Subject: yet another desk calculator has a bug!
Message-ID: <200@motel6.UUCP>
Date: Wed, 19-Mar-86 00:14:12 EST
Article-I.D.: motel6.200
Posted: Wed Mar 19 00:14:12 1986
Date-Received: Sat, 22-Mar-86 05:01:35 EST
Distribution: net
Organization: 5440 SE 41st, Portland, OR
Lines: 63

I thought this program was too simple to have bugs!  Alas I was
mistaken.  The following is a segment of the file expr.c, toward
the end of the routine eeval.  The changed lines are marked with '!'
marks.

Keith Packard
...!tektronix!reed!motel6!keith

-----------------------------------start of fix---------------------
	case INC:
		if (f->e_left == 0) {
			s = f->e_right->e_name;
			switch (s->s_type) {
			case UNDEF:
				s->s_type = VARTYPE;
			case VARTYPE:
				r = s->s_value;
				s->s_value += 1;
				break;
			case STACKTYPE:
				r = framep[s->s_offset];
				framep[s->s_offset] += 1;
			}
			return r;
		} else {
!			s = f->e_left->e_name;
			switch (s->s_type) {
			case UNDEF:
				s->s_type = VARTYPE;
			case VARTYPE:
				return (s->s_value += 1);
			case STACKTYPE:
				return (framep[s->s_offset] += 1);
			}
		}
	case DEC:
		if (f->e_left == 0) {
			s = f->e_right->e_name;
			switch (s->s_type) {
			case UNDEF:
				s->s_type = VARTYPE;
			case VARTYPE:
				r = s->s_value;
				s->s_value -= 1.0;
				break;
			case STACKTYPE:
				r = framep[s->s_offset];
				framep[s->s_offset] -= 1.0;
			}
			return r;
		} else {
!			s = f->e_left->e_name;
			switch (s->s_type) {
			case UNDEF:
				s->s_type = VARTYPE;
			case VARTYPE:
				return (s->s_value -= 1.0);
			case STACKTYPE:
				return (framep[s->s_offset] -= 1.0);
			}
		}

----------------------------------end of fix---------------------------------