132141 - Occurences of uninitialized variables being used before being set (in content/xul and layout/xul)

Status: RESOLVED DUPLICATE of bug 59652

(Core :: XUL, defect)

Description

[Aleksey Nogin]

This bug is just for the "xxx might be used uninitialized" warnings in various
source files in content/xul and layout/xul directories.
Currently (http://tinderbox.mozilla.org/SeaMonkey/warn1016552220.1515.html -
Tue, 19 Mar 2002 10:37 EST) TBox shows the following warnings:

content/xul/templates/src/nsTemplateMatchSet.cpp:257
 `class nsTemplateMatch ** last' might be used uninitialized in this function

layout/xul/base/src/nsBoxFrame.cpp:1715
 `nscoord onePixel' might be used uninitialized in this function

layout/xul/base/src/nsBoxToBlockAdaptor.cpp:598
 `nsresult rv' might be used uninitialized in this function

layout/xul/base/src/nsTextBoxFrame.cpp:355
 `nscolor overColor' might be used uninitialized in this function

layout/xul/base/src/nsTextBoxFrame.cpp:356
 `nscolor underColor' might be used uninitialized in this function

layout/xul/base/src/nsTextBoxFrame.cpp:357
 `nscolor strikeColor' might be used uninitialized in this function

Comment 1

[Aleksey Nogin]

Bug 59652 is the meta-bug tracking the fight against these (potentially very
nasty) warnings; bug 59675 is for warning in layout and bug 126457 is for
warnings in content.

Comment 2

[Pratik]

Of the warnings stated in comment 0, the following doesn't exist anymore

layout/xul/base/src/nsBoxToBlockAdaptor.cpp:598
 `nsresult rv' might be used uninitialized in this function

A simple patch to address the remaining warnings coming up.

Comment 3

[Pratik]

Attachment: patch to get rid of the warnings, v1

Comment 4

[Christopher Aillon (sabbatical, not receiving bugmail)]

Comment on attachment 110589 [details] [diff] [review]
patch to get rid of the warnings, v1

>Index: content/xul/templates/src/nsTemplateMatchSet.cpp

>-        nsTemplateMatch** last;
>+        nsTemplateMatch** last = nsnull;

Maybe I'm missing something, but why is this variable even needed?


>Index: layout/xul/base/src/nsBoxFrame.cpp

>-  nscoord onePixel;
>+  nscoord onePixel = NSIntPointsToTwips(0);

It seems strange to store what equates to 0 pixels into a variable named
onePixel.  Rather than initialize it here, why not move the declaration and
initialization to the block where it's actually used?  E.g. change:

  nscoord onePixel;
  if (foo) {
    ...
    onePixel = NSIntPixelsToTwips(1, p2t);
    ...
  }
  ...
  if (foo) {
    y = cr.y + onePixel;
    ...
  }

to:

  if (foo) {
    ...
  }
  ...
  if (foo) {
    nscoord onePixel = ...
    y = cr.y + onePixel;
    ...
  }

Comment 5

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

I think I already have the latter change in my patch to bug 186953, at least if
we're talking about the same file.

Comment 6

[Serge Gautherie (:sgautherie)]

(In reply to comment #5)
> I think I already have the latter change in my patch to bug 186953, at least if

Verified: <layout/xul/base/src/nsBoxFrame.cpp>, comment 4 |onePixel| fix was
checked in in bug 186953 :-)

Obsoleted r- patch v1: <nsTemplateMatchSet.cpp> and <nsTextBoxFrame.cpp>
warnings still exist: moving their fixes to bug 126457 and bug 59675 respectively.


*** This bug has been marked as a duplicate of 59652 ***