From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michael Witten <mfwitten@gmail.com>
Subject: Re: [RFC 2/2] Future Proofing: Pass around pointers to either functions or data
Date: Wed, 30 Mar 2011 15:02:28 +0000
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Cc: git@vger.kernel.org
To: Erik Faye-Lund <kusmabite@gmail.com>
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On Wed, 30 Mar 2011 12:09:46 +0200, Erik Faye-Lund <kusmabite@gmail.com> wrote:
> On Tue, Mar 29, 2011 at 5:28 PM, Michael Witten <mfwitten@gmail.com> wrote:
>> +#define ALT_ODB_FN_INFO_FUNC(variable, function) \
>> +       union alt_odb_fn_info variable = { \
>> +               .func = (alt_odb_fn_cb)function \
>> +       }
>> +#define ALT_ODB_FN_INFO_DATA(variable, data_) \
>> +       union alt_odb_fn_info variable = { \
>> +               .data = data_ \
>> +       }
>
> We try to stay away from C99 features like this, as it doesn't work on
> all compilers we target.

How about changing it to this:

#define ALT_ODB_FN_INFO_FUNC(variable, function) \
	union alt_odb_fn_info variable; do { \
		variable.func = (alt_odb_fn_cb)function; \
	} while (0)
#define ALT_ODB_FN_INFO_DATA(variable, data_) \
	union alt_odb_fn_info variable; do { \
		variable.data = data_ \
	} while (0)