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    SubjectRe: checkpatch, a patch checking script.
    On Wed, 2 May 2007 21:55:16 +0200 (CEST)
    Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> wrote:

    > On Wed, 2 May 2007, Andrew Morton wrote:
    > > On Wed, 2 May 2007 17:32:49 +0200 (CEST)
    > > Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> wrote:
    > >
    > > > On Wed, 2 May 2007, Christoph Hellwig wrote:
    > > > > On Wed, May 02, 2007 at 04:28:27PM +0200, Geert Uytterhoeven wrote:
    > > > > > - Check for GNU extension __FUNCTION__
    > > > >
    > > > > __FUNCTION__ is prefered over __func__
    > > >
    > > > Is there a reason for that?
    > > > - __FUNCTION__ is a GNU extension
    > > > - __func__ is C99
    > > > - __func__ is shorter to type ;-)
    > > >
    > >
    > > In that case we should use __func__.
    > >
    > > But we discussed this at some length 3-4 years ago and decided to use
    > > __FUNCTION__. I don't remember why. Perhaps problems with gcc support for
    > > __func__?
    >
    > I tried gcc 2.95/3.2/3.3/3.4/4.0/4.1, they all recognize __func__ and
    > __FUNCTION__, like in e.g. printf("%s", __func__);
    >
    > > (It could have been that compile-time string concatenation was involved:
    > >
    > >
    > > printf("xxx" __FILE__); /* works */
    > > printf("xxx" __FUNCTION__); /* doesn't */
    > >
    > > Or not.)
    >
    > Yep, when trying concatenation, I got:
    > - 2.95: works fine
    > - 3.2:
    > syntax error before "__func__"
    > warning: concatenation of string literals with __FUNCTION__ is deprecated
    > - 3.3:
    > error: syntax error before "__func__"
    > warning: concatenation of string literals with __FUNCTION__ is deprecated
    > - 3.4/4.0:
    > error: syntax error before "__func__"
    > error: syntax error before "__FUNCTION__"
    > - 4.1:
    > error: expected ')' before '__func__'
    > error: expected ')' before '__FUNCTION__'
    >
    > Hence gcc 3.2 and up treat __func__ like the a variable, as per C99, while
    > __FUNCTION__ has been moving from a virtual preprocessor definition in 2.95 to
    > a variable, like __func__.
    >
    > So in the end it doesn't matter, as concatenation has been fixed in the Linux
    > source tree anyway.
    >

    Great, thanks for working all that out.

    So __func__ it is. In new code. However "convert __FUNCTION__ to
    __func__" patches will be cheerfully ignored - life is too short.


    err, kernel.h has

    /* Trap pasters of __FUNCTION__ at compile-time */
    #define __FUNCTION__ (__func__)

    -
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