900209 - Element.cpp:1969:59 [-Wformat=] format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'nsEventStates::InternalType {aka long unsigned int}'

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Daniel Holbert [:dholbert]]

My debug build spams this warning:
{
content/base/src/Element.cpp:1969:59 [-Wformat=] format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'nsEventStates::InternalType {aka long unsigned int}'
}

which, as it turns out, is the only remaining warning that I see for all of /content/base.

The code in question is:
> 1969   fprintf(out, " state=[%llx]", State().GetInternalValue());
 http://mxr.mozilla.org/mozilla-central/source/content/base/src/Element.cpp#1969
where GetInternalValue() returns InternalType, which is typedefed to uint64_t (which, on 64-bit linux, is a typedef for to "unsigned long", not unsigned-long-long, as the warning indicates.

This is pretty easy to fix -- we can just static_cast to unsigned long long, to *force* the arg to match the format string. The minor downside is that on 64-bit architectures, this will do some unnecessary promotion, but that should be harmless, since the promotion is safe and this is in a chunk of debugging code anyway (where perf isn't a factor).

Comment 1

[Daniel Holbert [:dholbert]]

Attachment: fix v1

Comment 2

[Daniel Holbert [:dholbert]]

(Note: bug 730805 has a better way of doing this, but it seems to have stagnated.)

Comment 3

[Daniel Holbert [:dholbert]]

https://tbpl.mozilla.org/?tree=Try&rev=bda2669dc092

Comment 4

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/8e78d28f3b46

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/8e78d28f3b46