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List of issues#1849 Large script(s) seem to cause possible overflow error when attempting to save modifications
Author: 
Badfitz66
Badfitz66Date created:
Type: bug
Visibility: Everybody
Assigned to:
Labels: AS1/2Value Too Large
State: closed 
> What steps will reproduce the problem?
Download Main.swf
Go into sprites and scroll down until you see "frame 2"
Expand frame 2 and open the DoAction script
Modify the script in anyway so you can save it (add a comment or whatever)
> What is the expected output? What do you see instead?
Upon clicking save, the file should (obviously) save, but instead the program freezes for
a few seconds and then continues without saving (doesn't exit editor mode either).
> What version of the product are you using? Is it "nightly build"? Which operating system
do you have?
I am on nightly build 2029 but this issue has persisted for a lot of versions as far as I
know
> Please provide any additional information below. If the problem is related to a SWF
file, attach it here, otherwise we can't help you.
From my (very bad) attempt at debugging this error, it seems to be some sort of overflow
error related to saving. Possibly due to the enormous size of this script file.
Main.swf (14,997 KiB)
In such cases of editor not saving, please check lower right corner of the ffdec window -
in case of error, there is red icon, when you click it, it shows list of generated errors.
(see attachment)
ActionScript is saved with instructions so called "actions". Each action can have
parameters up to 65655 bytes. It seems that in this code, some compiled action exceeds
this limit and thus cannot be saved.
We say its X is too large for 16bit unsigned integer (UI16).
So you are right that it has something to do with enormous size of this script.
In original data, it is probably saved okay, but keep in mind that we always do total
recompilation of the script using our own decompiler and then compiler which can behave
differently than original compiler which produced this SWF.
Unfortunately, I cannot help you with this much.
I must say that it is very uncomfortable that there is no specific message popup that tell
you this,
but on the other hand, this problem (about writing larger value) can happen in many
situations (not even editing ActionScript) and we cannot handle all of them properly or
even display message.
So we stick with error in the error notifications area.
I would like to not touch the (de)compiler functions of the ffdec and do not optimize it
anyway,
since it is 1) very hard to do and 2) can lead to errors even on smaller scripts.
ffdec_value_too_large_ui16.png (245 KiB)In nightly 2124 we display error dialog during saving such script informing about the
situation.
(Instead of silently raising exception)
State: new→upgraded
State: upgraded→closed