32370 - Variables used before they are set in nsJSXUL*

Status: VERIFIED WORKSFORME

(Core :: Security, defect, P3)

Description

[jim_nance]

My compiler discovered several places in the code where variables
were being used before they were set.  I took a look at the code
and the compiler was right.  These look like real bugs.  I have
attached a patch that fixes these problems.

Comment 1

[jim_nance]

Attachment: Patch to fix bugs

Comment 2

[Richard Zach]

CVS log says all these belong to norris.

Comment 3

[Norris Boyd]

The change in nsHTMLSelectElement.cpp appears already to have been made.

All the nsJSXUL* files are generated by the DOM idl compiler. I tweaked that
recently; thanks for catching the problems. I'll fix it by redoing the compiler.

Comment 4

[Norris Boyd]

actually, when I look at the latest version on the tip, all the declarations of
nsresult rv are now initialized to NS_OK. So there shouldn't be any reads of
uninitialized variables.

I don't think I'll try to actually remove the declarations and usages of rv from
the places you indicate. It's hard to detect those situations in the stub
generator (see mozilla/dom/tools/JSStubGen.cpp), and a halfway decent optimizing
compiler should do constant propagation and dead code elimination to produce the
same effect.

Comment 5

[John Unruh]

Verified per norris' comments.