Re: [Qemu-devel] [PATCH] build: compile gtk.c with special CFLAGS

[Blue Swirl]

On Mon, Mar 4, 2013 at 8:29 PM, Anthony Liguori <address@hidden> wrote:
> Blue Swirl <address@hidden> writes:
>
>> On Sun, Mar 3, 2013 at 9:03 PM, Anthony Liguori <address@hidden> wrote:
>>> Blue Swirl <address@hidden> writes:
>>>
>>>> Compile gtk.c with special CFLAGS instead of disabling -Werror globally.
>>>>
>>>> Signed-off-by: Blue Swirl <address@hidden>
>>>
>>> I thought Kevin's pragma trick solved this problem?
>>
>> Not in all cases it seems.
>>
>>>
>>> Are you attempting to avoid disabling Werror when prgram isn't
>>> available?  That seems to defeat the purpose of doing the pragma thing
>>> to begin with.
>>
>> When the pragma works, there should not be any need to disable -Werror
>> or other flags. If the pragmas are not available, we can disable the
>> offending flags only for gtk.c and keep them for the rest of the
>> build.
>
> The idea of the pragma is that gtk.c is the only place that will need
> this in the future.

It's also the only file that needs GTK_CFLAGS. For simplicity, that
could contain also QEMU_CFLAGS, filtered for offending flags.

> So either we like the pragma approach and just live with disabling
> Werror on older GCCs or there's no point in doing the pragma approach in
> the first place.
>
> Since this is an issue only with older GCCs, I see no reason to care
> about disabling Werror really.  It's a problem that solves itself over time.
>
> Regards,
>
> Anthony Liguori
>
>>
>>>
>>> Regards,
>>>
>>> Anthony Liguori
>>>
>>>> ---
>>>>  configure        |   12 +++++++++++-
>>>>  ui/Makefile.objs |    2 +-
>>>>  2 files changed, 12 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/configure b/configure
>>>> index 19738ac..2a043d6 100755
>>>> --- a/configure
>>>> +++ b/configure
>>>> @@ -3139,6 +3139,7 @@ fi
>>>>  # the build doesn't fail anyway.
>>>>
>>>>  pragma_disable_unused_but_set=no
>>>> +gtk_special_cflags=no
>>>>  cat > $TMPC << EOF
>>>>  #pragma GCC diagnostic ignored "-Wunused-but-set-variable"
>>>>  #pragma GCC diagnostic ignored "-Wstrict-prototypes"
>>>> @@ -3150,7 +3151,7 @@ EOF
>>>>  if compile_prog "-Werror" "" ; then
>>>>      pragma_diagnostic_available=yes
>>>>  else
>>>> -    werror=no
>>>> +    gtk_special_cflags=yes
>>>>  fi
>>>>
>>>>  ########################################
>>>> @@ -3845,6 +3846,15 @@ echo "WINDRES=$windres" >> $config_host_mak
>>>>  echo "LIBTOOL=$libtool" >> $config_host_mak
>>>>  echo "CFLAGS=$CFLAGS" >> $config_host_mak
>>>>  echo "QEMU_CFLAGS=$QEMU_CFLAGS" >> $config_host_mak
>>>> +if test "$gtk_special_cflags" = "yes"; then
>>>> +  # Our compiler doesn't support #pragmas to suppress warnings and GTK
>>>> +  # can't be fixed, so compile GTK files with special CFLAGS
>>>> +  echo "GTK_SPECIAL_CFLAGS=$QEMU_CFLAGS" | \
>>>> +    sed -e 's/-Wstrict-prototypes//g' \
>>>> +        -e 's/-Wunused-but-set-variable//g' >> $config_host_mak
>>>> +else
>>>> +  echo "GTK_SPECIAL_CFLAGS=$QEMU_CFLAGS" >> $config_host_mak
>>>> +fi
>>>>  echo "QEMU_INCLUDES=$QEMU_INCLUDES" >> $config_host_mak
>>>>  if test "$sparse" = "yes" ; then
>>>>    echo "CC           := REAL_CC=\"\$(CC)\" cgcc"       >> $config_host_mak
>>>> diff --git a/ui/Makefile.objs b/ui/Makefile.objs
>>>> index 6ddc0de..c9aa1e6 100644
>>>> --- a/ui/Makefile.objs
>>>> +++ b/ui/Makefile.objs
>>>> @@ -19,4 +19,4 @@ $(obj)/sdl.o $(obj)/sdl_zoom.o: QEMU_CFLAGS += 
>>>> $(SDL_CFLAGS)
>>>>
>>>>  $(obj)/cocoa.o: $(SRC_PATH)/$(obj)/cocoa.m
>>>>
>>>> -$(obj)/gtk.o: QEMU_CFLAGS += $(GTK_CFLAGS) $(VTE_CFLAGS)
>>>> +$(obj)/gtk.o: QEMU_CFLAGS = $(GTK_SPECIAL_CFLAGS) $(GTK_CFLAGS) 
>>>> $(VTE_CFLAGS)
>>>> --
>>>> 1.7.2.5
>>>
>