[Mesa-dev] [PATCH] xlib: Do not undefine _R, _G, and _B.

[Vinson Lee]

On Sat, Oct 27, 2012 at 7:15 PM, Kenneth Graunke <kenneth at whitecape.org> wrote:
> On 10/27/2012 01:01 PM, Vinson Lee wrote:
>>
>> Fixes build error on Cygwin and Solaris. _R, _G, and _B are used in
>> ctype.h on those platforms.
>>
>> Signed-off-by: Vinson Lee <vlee at freedesktop.org>
>> ---
>>   src/mesa/drivers/x11/xfonts.c |    3 ---
>>   1 files changed, 0 insertions(+), 3 deletions(-)
>>
>> diff --git a/src/mesa/drivers/x11/xfonts.c b/src/mesa/drivers/x11/xfonts.c
>> index 9957e89..a92d24a 100644
>> --- a/src/mesa/drivers/x11/xfonts.c
>> +++ b/src/mesa/drivers/x11/xfonts.c
>> @@ -41,9 +41,6 @@
>>   /* Some debugging info.  */
>>
>>   #ifdef DEBUG
>> -#undef _R
>> -#undef _G
>> -#undef _B
>>   #include <ctype.h>
>>
>>   int debug_xfonts = 0;
>
>
> I'm somewhat skeptical that ctype.h actually needs _R, _G, and _B macros
> defined...and if it does, I'm -really- skeptical that we're #define'ing them
> to the expected values.  We probably define macros that have a different
> meaning...


I think what is happening is ctype.h is already include indirectly
through another header. xfonts.c undefines _B. dump_font_struct uses
the function isprint which is a macro from ctype.h that uses _B. The
build error occurs because _B was undefined.

Here is the build error.
src/mesa/drivers/x11/xfonts.c: In function ‘dump_font_struct’:
src/mesa/drivers/x11/xfonts.c:69:12: error: ‘_B’ undeclared (first use
in this function)

xfonts.c
    60  static void
    61  dump_font_struct(XFontStruct * font)
[...]
    68     printf("default_char = %c (\\%03o)\n",
    69            (char) (isprint(font->default_char) ?
font->default_char : ' '),
    70            font->default_char);

ctype.h
    40  #define _B      0200
[...]
    67  #define isprint(__c)    (__ctype_lookup(__c)&(_P|_U|_L|_N|_B))


Kenneth, what do you think is the right approach here to fix the build error?