674494 - Uninitialised variable in ThebesLayerBuffer causes incorrect marking of mDidSelfCopy flag

Status: RESOLVED FIXED

(Core :: Graphics, defect)

Description

[Chris Lord [:cwiiis]]

At the beginning of ThebesLayerBuffer::BeginPaint, the returned 'PaintState' variable is uninitialised. As not all of its fields are set, this can cause the 'mDidSelfCopy' flag to be incorrectly marked.

Patch incoming...

Comment 1

[Chris Lord [:cwiiis]]

Attachment: Fix uninitialised PaintState return variable

Comment 2

[Chris Lord [:cwiiis]]

Attachment: Fix uninitialised PaintState return variable

Sorry, another patch was accidentally combined.

Comment 3

[Matt Woodrow (:mattwoodrow)]

I think I'd rather add a constructor to set mDidSelfCopy to false, good catch though

Comment 4

[Chris Lord [:cwiiis]]

Attachment: Fix uninitialised PaintState return variable by adding a constructor

Updated patch that uses a constructor.

Comment 5

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 552323 [details] [diff] [review]
Fix uninitialised PaintState return variable by adding a constructor

Review of attachment 552323 [details] [diff] [review]:
-----------------------------------------------------------------

::: gfx/layers/ThebesLayerBuffer.h
@@ +114,5 @@
>    struct PaintState {
> +    PaintState()
> +      : mContext(nsnull)
> +      , mRegionToDraw()
> +      , mRegionToInvalidate()

You shouldn't need to explicitly construct these 3, they should all default to the correct values.

Comment 6

[Chris Lord [:cwiiis]]

Attachment: Fix uninitialised PaintState return variable by adding a constructor (final?)

Assuming this is good to go, could you push? I don't have L3 access yet.

Comment 7

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 553142 [details] [diff] [review]
Fix uninitialised PaintState return variable by adding a constructor (final?)

Looks good!

I'll land this on incoming this afternoon.

Comment 8

[Matt Woodrow (:mattwoodrow)]

http://hg.mozilla.org/integration/mozilla-inbound/rev/f345becaf55b

Comment 9

[Marco Bonardo [:mak]]

http://hg.mozilla.org/mozilla-central/rev/f345becaf55b