[comp.sys.amiga.tech] An ARexx bug ?

sutela@tucos.UUCP (Kari Sutela) (05/16/89)

I noticed this bug when I tested the graph.rexx program which was distributed
with rexxarplib v2.2. I noticed that the program would freeze at a statement
which was something like this: "somevar = -x**2". Immediately when x becomes
zero, the program will freeze. BTW, I don't remember whether this bug occurred
in graph.rexx or testgraphs.rexx.

Anyway, I researched a bit more and found that this one-liner will also 
cause the problem (even after remlib()'ing rexxarplib and rexxmathlib):

/* bug.rexx */
say -0

The program never stops and system performance will decrease dramatically.
I started XOper and noticed that rexx was eating about 40% of CPU-cycles.

Has anybody else noticed this bug? I reinstalled rexx and 1.3 mathieedoubbas.
library straight from the distribution disks, but this didn't cure it, so
I guess there indeed is a bug in rexxsyslib.library - is there a patch to
cure this? I guess mathieedoubbas.library can't be guilty (haven't checked,
yet)?

- Kari Sutela 
- sutela@tucos.cs.utu.fi OR lk-kari@fintuvm.utu.fi OR lk-kari@fintuvm.BITNET

cmcmanis%pepper@Sun.COM (Chuck McManis) (05/17/89)

In article <895@tucos.UUCP> sutela@tucos.cs.utu.fi writes:
>/* bug.rexx */
>say -0

Known bug, ARexx can't handle negative zero. Bill Hawes knows about
it and has promised to fix it for the next release.

--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.
"A most excellent barbarian ... Genghis Kahn!"

lphillips@lpami.wimsey.bc.ca (Larry Phillips) (05/17/89)

In <895@tucos.UUCP>, sutela@tucos.UUCP (Kari Sutela) writes:
>I noticed this bug when I tested the graph.rexx program which was distributed
>with rexxarplib v2.2. I noticed that the program would freeze at a statement
>which was something like this: "somevar = -x**2". Immediately when x becomes
>zero, the program will freeze. BTW, I don't remember whether this bug occurred
>in graph.rexx or testgraphs.rexx.
>
>Anyway, I researched a bit more and found that this one-liner will also 
>cause the problem (even after remlib()'ing rexxarplib and rexxmathlib):
>
>/* bug.rexx */
>say -0
>
>The program never stops and system performance will decrease dramatically.

It doesn't hang for me, so it may be a bug in any one of the libs or in ARexx
itself. I am testing a newer version, so it may have been fixed. I know there
are a few squashed bugs in rexxsyslib and ARexx itself.

-larry

--
  - Don't tell me what kind of a day to have! -
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|   //   Larry Phillips                                                |
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