1195154 - xpcom/tests/TestNsRefPtr.cpp(455): error C2666: 'operator !=': 3 overloads have similar conversions

Status: RESOLVED FIXED

(Core :: XPCOM, defect)

Description

[Xidorn Quan [:xidorn] UTC+10]

Meet an error when compiling on VC14 today:
> xpcom/tests/TestNsRefPtr.cpp(455): error C2666: 'operator !=': 3 overloads have similar conversions
> obj-firefox\dist\include\mozilla/nsRefPtr.h(576): note: could be 'bool operator !=<Foo>(const nsRefPtr<Foo> &,detail::nsRefPtrZero *)'
> xpcom/tests/TestNsRefPtr.cpp(455): note: while trying to match the argument list '(nsRefPtr<Foo>, int)'
> xpcom/tests/TestNsRefPtr.cpp(457): error C2666: 'operator !=': 3 overloads have similar conversions
> obj-firefox\dist\include\mozilla/nsRefPtr.h(584): note: could be 'bool operator !=<Foo>(detail::nsRefPtrZero *,const nsRefPtr<Foo> &)'
> xpcom/tests/TestNsRefPtr.cpp(457): note: while trying to match the argument list '(int, nsRefPtr<Foo>)'
> xpcom/tests/TestNsRefPtr.cpp(459): error C2666: 'operator ==': 3 overloads have similar conversions
> obj-firefox\dist\include\mozilla/nsRefPtr.h(560): note: could be 'bool operator ==<Foo>(const nsRefPtr<Foo> &,detail::nsRefPtrZero *)'
> xpcom/tests/TestNsRefPtr.cpp(459): note: while trying to match the argument list '(nsRefPtr<Foo>, int)'
> xpcom/tests/TestNsRefPtr.cpp(461): error C2666: 'operator ==': 3 overloads have similar conversions
> obj-firefox\dist\include\mozilla/nsRefPtr.h(568): note: could be 'bool operator ==<Foo>(detail::nsRefPtrZero *,const nsRefPtr<Foo> &)'
> xpcom/tests/TestNsRefPtr.cpp(461): note: while trying to match the argument list '(int, nsRefPtr<Foo>)'
> xpcom/tests/TestNsRefPtr.cpp(504): error C2666: 'operator ==': 3 overloads have similar conversions
> obj-firefox\dist\include\mozilla/nsRefPtr.h(560): note: could be 'bool operator ==<Foo>(const nsRefPtr<Foo> &,detail::nsRefPtrZero *)'
> xpcom/tests/TestNsRefPtr.cpp(504): note: while trying to match the argument list '(nsRefPtr<Foo>, int)'

Not sure what's the best way to fix.

Comment 1

[Bas Schouten (:bas.schouten)]

I'm not so certain the compiler is wrong here.. conversion to a random T* seems equally acceptable as a conversion to an nsRefPtr...

Comment 2

[Xidorn Quan [:xidorn] UTC+10]

Only failing compiling on this test may indicate that we don't really use this kind of code elsewhere. Thus, I guess we can probably simply remove this test code as well as the overloads.

Comment 3

[Xidorn Quan [:xidorn] UTC+10]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=221b9f682365

Comment 4

[Xidorn Quan [:xidorn] UTC+10]

Attachment: MozReview Request: Bug 1195154 - Replace operator overloads for comparing nsRefPtr to 0 with those for comparing to nullptr.

Bug 1195154 - Replace operator overloads for comparing nsRefPtr to 0 with those for comparing to nullptr.

Comment 5

[Nathan Froyd [:froydnj]]

Comment on attachment 8649077 [details]
MozReview Request: Bug 1195154 - Replace operator overloads for comparing nsRefPtr to 0 with those for comparing to nullptr.

https://reviewboard.mozilla.org/r/16351/#review14715

Nice, thanks for doing this.  Can you file a followup for the same treatment of the overloads for nsCOMPtr/nsAutoPtr/nsAutoArrayPtr/nsHtml5RefPtr, please?

Comment 6

[Xidorn Quan [:xidorn] UTC+10]

url:        https://hg.mozilla.org/integration/mozilla-inbound/rev/20c6f74296e23869759dbfd8cbad8456be59fbae
changeset:  20c6f74296e23869759dbfd8cbad8456be59fbae
user:       Xidorn Quan <[e-mail]>
date:       Wed Aug 19 09:09:08 2015 +1000
description:
Bug 1195154 - Replace operator overloads for comparing nsRefPtr to 0 with those for comparing to nullptr. r=froydnj

Comment 7

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/20c6f74296e2

Comment 8

[Nigel Babu [:nigelb]]

Backed out in https://hg.mozilla.org/integration/mozilla-inbound/rev/abdb239a6d4d

Comment 9

[Bob Clary [:bc] (inactive)]

nigelb: The backout does not appear to have helped with the regression in bug 1196115. I think we can reland this.

Comment 10

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

Relanded https://hg.mozilla.org/integration/mozilla-inbound/rev/823aa80c5ffa

Comment 11

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/823aa80c5ffa