cannot `lossage-size` a large number

Question

emacs-28.2; win 11

$ emacs -Q

If I use most-positive-fixnum:
```
(lossage-size most-positive-fixnum) 
```
Emacs will emit: Value must be >= 100 in the echo area.
If I use a modest number:
```
(lossage-size (/ most-positive-fixnum 10)) 
```
Emacs will crash immediately.

I just want to use most-positive-fixnum to indicate that I won't limit the size of lossage.

Drew · Accepted Answer · 2023-03-19 21:55:01Z

If Emacs crashes then there's a bug in Emacs (in its C code). Do M-x report-emacs-bug immediately, in particular providing a recipe that starts with emacs -Q (no init file).
I tried emacs -Q followed by (lossage-size (/ most-positive-fixnum 10)) in Emacs 28.2 on MS Windows, and it didn't crash. It simply returned this value: 858993459.
Raising an error for (lossage-size most-positive-fixnum) seems like a bug, to me. Certainly the value of most-positive-fixnum is at least 100. You might want to report this.

You apparently reported this as Emacs bug#62277, and as a result it's now been fixed for the upcoming Emacs 29 release. Thanks!

Did you watch the memory usage ? The memory of my Emacs increased fast when eval (lossage-size (/ most-positive-fixnum 10)). — summertime
– summertime, Commented Mar 19, 2023 at 16:56
That's not a crash. And after it returned - or even if you used C-g to interrupt its evaluation - did you try evaluating it again? — Drew
– Drew, Commented Mar 19, 2023 at 16:59
No, I cannot try again during the same session because my Emacs just crashed, then a window (here window is a window in MS-Windows) popped up (asking me whether to debug emacs.exe). I don't why the memory usage will increase. — summertime
– summertime, Commented Mar 19, 2023 at 17:04
Report the problem you see: M-x report-emacs-bug, whether it's actually a crash or something different. — Drew
– Drew, Commented Mar 19, 2023 at 17:07

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