Bug 43191 – [Qt] Treat warnings as errors by default for gcc

• Component: Tools / Tests
• Status: RESOLVED WONTFIX

[Csaba Osztrogonác]

I create this bug because of discussion in https://bugs.webkit.org/show_bug.cgi?id=30958 .

I agree with Laszlo, we should treat warnings as errors 
to avoid breaking other platforms accidentally.

The main goal of this patch is adding -Werror to QMAKE_CFLAGS,
but it depends on fixing dozens of warning. First we can focus
on x86-linux and x86-windows platforms and then ARM-linux and 
other platforms.

[Csaba Osztrogonác]

(In reply to comment #9 in https://bugs.webkit.org/show_bug.cgi?id=30958)
> My only concern would be the extra pressure to fix these warnings to keep the bot green. CCing Ossy to see what he think.
 
> A somewhat relaxed version of this - which I think we should do - is to start treating warnings as errors by default (at least on platforms where this is realistic like i386) but have a provision (e.g. environment variable) not to do this for the build bot.
 
> This will force most developers to look into the warning but does not put extra pressure on the bot.

I absolutely agree with Laszlo, it is a good way to solve this bug.

[Csaba Osztrogonác]

*** Bug 37916 has been marked as a duplicate of this bug. ***

[Csaba Osztrogonác]

Created attachment 66858 [details]
enable -Werror on x86/Linux/GCC platforms

I think it's time to enable -Werror on x86/Linux/GCC platforms
after https://bugs.webkit.org/show_bug.cgi?id=45373 fixed.

The next steps will be Windows/GCC and ARM/Linux/GCC after all warnings fixed.

[Andreas Kling]

Comment on attachment 66858 [details]
enable -Werror on x86/Linux/GCC platforms

r=me

I always feel silly when the EWS slaps me about some warning that my own machine knew about but wasn't loud enough.

[Csaba Osztrogonác]

Comment on attachment 66858 [details]
enable -Werror on x86/Linux/GCC platforms

cq-, because I will land manually after 
https://bugs.webkit.org/show_bug.cgi?id=45373 fixed

[Csaba Osztrogonác]

Comment on attachment 66858 [details]
enable -Werror on x86/Linux/GCC platforms

Clearing flags on attachment: 66858

Committed r66972: <http://trac.webkit.org/changeset/66972>

[Csaba Osztrogonác]

(In reply to comment #6)
> (From update of attachment 66858 [details])
> Clearing flags on attachment: 66858
> 
> Committed r66972: <http://trac.webkit.org/changeset/66972>
And a buildfix landed in http://trac.webkit.org/changeset/66990 ,
because linux-g++ is true when you build for maemo inside sbox,
but we didn't want to enable -Werror for it now.

I didn't run into this issue, because linux-g++ is false 
for ARM cross compiling, but linux-arm-g++ is true.

[Laszlo Gombos]

Very nice, thanks for all this work !