the fround word push its result to data stack.

[edakawa]

Dear Mr. Phil Burk,

I'm a user of pForth and very happy to use it. By the way, I have a question
about the following parts,

$ pforth -q
7.7e fround . 8

7.7e fround f. 0.0000000 Stack<10> 8
THROW code = -45
Float Stack underflow!
bye
$

Is this the correct behavior? I expected the following behavior,

$ pforth -q
7.7e fround f. 8.000000
bye
$

I would like to think the fround word should push its result to floating point
stack. If this question was a known issue, I did very rudely, so I'm very sorry.

Finally, I modified csrc/pfinnrfp.h to get my expected behavior,

$ diff -C 2 pfinnrfp.h.orig pfinnrfp.h
*** pfinnrfp.h.orig     Mon Oct 28 15:50:40 2019
--- pfinnrfp.h  Mon Oct 28 15:30:43 2019
***************
*** 207,213 ****

      case ID_FP_FROUND:
!         PUSH_TOS;
!         TOS = (cell_t)fp_round(FP_TOS);
!         M_FP_DROP;
          break;

--- 207,211 ----

      case ID_FP_FROUND:
!         FP_TOS = (PF_FLOAT) fp_round(FP_TOS);
          break;
$

Sincerely,
Hajime Edakawa

[philburk]

You are right! According to the latest standard here:

http://lars.nocrew.org/forth2012/floating/FROUND.html

Since it returned a rounded "integer" value I assumed it would be on the integer stack. Not so.

Fixing this will break any pForth program currently using FROUND. So I will need to make sure users are warned.

If this question was a known issue, I did very rudely, so I'm very sorry.

No. Even if it was a known issue it would not be rude. I want to improve pForth. So every bug report is helpful. Even questions are helpful because then I know where to improve the documentation. You reported a bug and gave me the fix. I am grateful.

[philburk]

HMSL uses FROUND. It will need to be changed.

https://github.com/philburk/hmsl/blob/34ef562ad3ac552e27620bffb2949d975f715a70/hmsl/fth/float_port.fth#L31

[edakawa]

Good to hear that. And,

No. Even if it was a known issue it would not be rude. I want to improve pForth. So every bug report is helpful. Even questions are helpful because then I know where to improve the documentation. You reported a bug and gave me the fix.

I really got courage from your comments. Thank you for giving me good advice!