1256559 - intl/locale/windows/nsWin32Locale.cpp(736): warning C4477: 'fprintf' : format string '%d' requires an argument of type 'int', but variadic argument 1 has type 'size_t'

Status: RESOLVED FIXED

(Core :: Internationalization, defect)

Description

[Gregory Szorc [:gps]]

Seeing multiple compiler warnings turned into errors when running Visual Studio 2015 Update 1 in automation.

 22:58:57     INFO -  nsWin32Locale.cpp
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(736): error C2220: warning treated as error - no 'object' file generated
 22:58:57     INFO -  Warning: C4477 in c:\builds\moz2_slave\try-w64-d-00000000000000000000\build\src\intl\locale\windows\nsWin32Locale.cpp: 'fprintf' : format string '%d' requires an argument of type 'int', but variadic argument 1 has type 'size_t'
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(736): warning C4477: 'fprintf' : format string '%d' requires an argument of type 'int', but variadic argument 1 has type 'size_t'
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(736): note: to simplify migration, consider the temporary use of /Wv:18 flag with the version of the compiler with which you used to build without warnings
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(736): note: consider using '%zd' in the format string
 22:58:57     INFO -  Warning: C4477 in c:\builds\moz2_slave\try-w64-d-00000000000000000000\build\src\intl\locale\windows\nsWin32Locale.cpp: 'fprintf' : format string '%d' requires an argument of type 'int', but variadic argument 2 has type 'size_t'
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(736): warning C4477: 'fprintf' : format string '%d' requires an argument of type 'int', but variadic argument 2 has type 'size_t'
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(736): note: to simplify migration, consider the temporary use of /Wv:18 flag with the version of the compiler with which you used to build without warnings
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(736): note: consider using '%zd' in the format string
 22:58:57     INFO -  Warning: C4477 in c:\builds\moz2_slave\try-w64-d-00000000000000000000\build\src\intl\locale\windows\nsWin32Locale.cpp: 'fprintf' : format string '%d' requires an argument of type 'int', but variadic argument 1 has type 'size_t'
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(740): warning C4477: 'fprintf' : format string '%d' requires an argument of type 'int', but variadic argument 1 has type 'size_t'
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(740): note: to simplify migration, consider the temporary use of /Wv:18 flag with the version of the compiler with which you used to build without warnings
 22:58:57     INFO -  c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/intl/locale/windows/nsWin32Locale.cpp(740): note: consider using '%zd' in the format string
22:58:57 INFO - c:/builds/moz2_slave/try-w64-d-00000000000000000000/build/src/config/rules.mk:930: recipe for target 'nsWin32Locale.obj' failed

Comment 1

[Gregory Szorc [:gps]]

Attachment: MozReview Request: Bug 1256559 - Disable C4477 to unblock compilation on VS2015; r?smontagu

As part of unblocking building with VS2015u1 in automation, I'm mass
disabling compiler warnings that are turned into errors. This is not
the preferred mechanism to fix compilation warnings. So hopefully
this patch never lands because someone insists on fixing the underlying
problem instead. But if it does land, hopefully the workaround is
only temporary.

Review commit: https://reviewboard.mozilla.org/r/39999/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/39999/

Comment 2

[Simon Montagu :smontagu]

Comment on attachment 8730560 [details]
MozReview Request: Bug 1256559 - Disable C4477 to unblock compilation on VS2015; r?smontagu

https://reviewboard.mozilla.org/r/39999/#review36775

Comment 3

[Simon Montagu :smontagu]

Attachment: Remove the warning by using %zd like the man said

I can't easily compile on Windows, but shouldn't this be enough to prevent the warning?

Comment 4

[Gregory Szorc [:gps]]

Comment on attachment 8730945 [details] [diff] [review]
Remove the warning by using %zd like the man said

Review of attachment 8730945 [details] [diff] [review]:
-----------------------------------------------------------------

I haven't touched C++ in a very, very long time. So I'm not appropriate to review this.

But I can push this patch to Try and let you know if it works.

Comment 5

[Gregory Szorc [:gps]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=4ffefc3c3cc5

Comment 6

[Gregory Szorc [:gps]]

Comment on attachment 8730945 [details] [diff] [review]
Remove the warning by using %zd like the man said

Review of attachment 8730945 [details] [diff] [review]:
-----------------------------------------------------------------

https://treeherder.mozilla.org/logviewer.html#?job_id=18126620&repo=try says this patch failed to clear the warning.

Comment 7

[Simon Montagu :smontagu]

Attachment: Remove the warning by using %zd like the man said ,v.2

But it does remove two warnings, so this version should clear the third one.

Comment 8

[Gregory Szorc [:gps]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=0eacddb070e1

Comment 9

[Gregory Szorc [:gps]]

Comment on attachment 8731073 [details] [diff] [review]
Remove the warning by using %zd like the man said ,v.2

Review of attachment 8731073 [details] [diff] [review]:
-----------------------------------------------------------------

This seems to have eliminated the warnings!

I'll drop my review requests. Please get review and land this ASAP to unblock VS2015.

Thank you for insisting on the proper fix.

Comment 10

[Jonathan Kew [:jfkthame]]

Comment on attachment 8731073 [details] [diff] [review]
Remove the warning by using %zd like the man said ,v.2

Review of attachment 8731073 [details] [diff] [review]:
-----------------------------------------------------------------

Does this work on VS2013? AFAICT, it probably won't...

https://connect.microsoft.com/VisualStudio/feedback/details/806338/vc-printf-and-scanf-should-support-z

So are we totally dropping VS2013 support at this point? If not, we need an alternative solution. (Given where this is being used, I'd think that just casting the size_t to an unsigned int and printing it with %u would be fine.)

Comment 11

[Gregory Szorc [:gps]]

I'm not sure when we're dropping VS2013. But I know people are anxious to do that so we can adopt more modern C++ features.

Code will need to work with both VS2013 and VS2015 for the interim. Or you can disable the warning.

Comment 12

[Jonathan Kew [:jfkthame]]

Attachment: To avoid VS2013 vs 2015 issues, just cast the size_t values to unsigned and print them with %u in the debug messages here

This should avoid the warnings, while remaining compatible with older VS releases (lacking %z). The numbers involved here will never be large enough to exceed a plain 'unsigned' value.

Comment 13

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/521e461d2eef

Comment 14

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/521e461d2eef