657354 - Javascript in Mozilla 1.7.13 Returns NaN after sometime

Status: RESOLVED INVALID

(Core :: JavaScript Engine, defect)

Description

[turokman555]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.17) Gecko/20110420 Firefox/3.6.17
Build Identifier: Mozilla 1.7.13

Hi,

I am running Mozilla 1.7.13 on PowerPC on Linux.   I can't upgrade due to hardware limitations and I am running into a bug that is very interesting.

After some period of time, running the modulus operator stops working and returns NaN for known good numbers.  I used syslog to verify that the numbers are real before the modulus operator.  I can't reproduce the bug in any easy way, but I can consistently reproduce it with a testcase for my custom hardware.

In short, the code snippet I am using, will fail after some period of time:

log(this.item);  // this is always 2 when it fails
log(this.length);  // this is always 3 when it fails
this.item = (this.item + 1) % this.length;  //this should be 3 % 3 and return 0, but it returns NaN

It seems like it could possibly very well be a memory / platform related issue.  But any advice on how to troubleshoot this would be great.



Reproducible: Always

Steps to Reproduce:
1.  Unfortunately, my test case is very custom to my hardware, and using an API to drive my hardware.  But I can tell you that I can reproduce it everytime, and the failure is always within the % operator.

2.  After I put in the fix to check for whether or not the % operator returns NaN, I see about 20 hours later a failure in the assignment operator.  

Actual Results:  
Modulus operator returns NaN instead of 0 after around 3 hours.

Expected Results:  
It should return 0

Again, I can't upgrade past 1.7.13, but I can tell you that free memory is very low on my system, and I am running this on a PowerPC board.

Comment 1

[Matthias Versen [:Matti]]

Mozilla1.7.13 is far behind the end of life and the PPC is platform is no longer supported with Gecko2.0.
That is the reason why i have to mark this report invalid.
I'm moving this to JS Engine, maybe a JS developer could answer your question but I doubt it.