svn commit: r334702 - head/sys/sys

[Ravi Pokala]

-----Original Message-----
From: <owner-src-committers at freebsd.org> on behalf of Benjamin Kaduk <bjkfbsd at gmail.com>
Date: 2018-06-06, Wednesday at 07:40
To: Ravi Pokala <rpokala at freebsd.org>
Cc: Mateusz Guzik <mjg at freebsd.org>, src-committers <src-committers at freebsd.org>, <svn-src-all at freebsd.org>, <svn-src-head at freebsd.org>
Subject: Re: svn commit: r334702 - head/sys/sys

> On Wed, Jun 6, 2018 at 6:35 AM, Ravi Pokala <rpokala at freebsd.org> wrote:
>> 
>> Hi Mateusz,
>> 
>> -----Original Message-----
>> From: <owner-src-committers at freebsd.org> on behalf of Mateusz Guzik <mjg at FreeBSD.org>
>> Date: 2018-06-06, Wednesday at 01:08
>> To: <src-committers at freebsd.org>, <svn-src-all at freebsd.org>, <svn-src-head at freebsd.org>
>> Subject: svn commit: r334702 - head/sys/sys
>> 
>>> ...
>>>  #ifdef _KERNEL
>>>  #define      malloc(size, type, flags) ({                                    \
>> 
>> Now that I'm taking another look at this, I'm confused as to why the entire macro expansion is inside parentheses? (The braces make sense, since this is a block with local variables which need to be contained.)
> 
> This is a gcc (and clang) extension to allow the macro body to be a code block -- standard C gets unhappy with just the curly braces.  https://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html is a maybe-relevant page that google found me.

"Neat." Thanks Ben.

-Ravi

> -Ben