742565 - nsRange.cpp:668:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

Status: RESOLVED FIXED

Description

[Daniel Holbert [:dholbert]]

Filing bug on these new build warnings:
> content/base/src/nsRange.cpp: In member function ‘virtual nsresult nsRange::ComparePoint(nsIDOMNode*, PRInt32, PRInt16*)’:
> content/base/src/nsRange.cpp:668:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
> content/base/src/nsRange.cpp: In member function ‘nsresult nsRange::SetStart(nsINode*, PRInt32)’:
> content/base/src/nsRange.cpp:932:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
> content/base/src/nsRange.cpp: In member function ‘nsresult nsRange::SetEnd(nsINode*, PRInt32)’:
> content/base/src/nsRange.cpp:996:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

In each case, it's something like:
> if (aOffset < 0 || aOffset > aParent->Length()) {
...where aOffset is signed and Length() returns an unsigned value.

This comparison would only be problematic if aOffset were negative; however, we're already ensuring it's nonnegative before we perform the comparison.  So we can just cast it to be a signed val for the purpose of the comparison.

Comment 1

[Daniel Holbert [:dholbert]]

Created attachment 612373 [details] [diff] [review]
fix

Comment 2

[Daniel Holbert [:dholbert]]

(In reply to Daniel Holbert [:dholbert] from comment #0)
> So we can just cast it to be a signed val for the purpose of the comparison.

(er I meant "cast it to be an _un_signed val" (which the attached patch does))

Comment 3

[Daniel Holbert [:dholbert]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/9082d2112975

Comment 4

[:Ehsan Akhgari (needinfo please, extremely long backlog, Away 8/18)]

https://hg.mozilla.org/mozilla-central/rev/9082d2112975