[Bug preprocessor/37549] gcc -E -dD prints predefined macros, contrary to docs

pinskia at gmail dot com gcc-bugzilla@gcc.gnu.org
Wed Sep 17 03:15:00 GMT 2008



------- Comment #1 from pinskia at gmail dot com  2008-09-17 03:13 -------
Subject: Re:   New: gcc -E -dD prints predefined macros, contrary to docs



Sent from my iPhone

On Sep 16, 2008, at 7:25 PM, "martinrb at google dot com"
<gcc-bugzilla@gcc.gnu.org 
 > wrote:

> The docs for preprocessor -dD flag states
>
>    `D'
>          Like `M' except in two respects: it does _not_ include the
>          predefined macros

I think what it means by predefines are the ones included on the  
command line that are defined by the user via -D.

>
>
> So one would expect -dD and -dM to differ substantially.
> But....
>
> (martinrb@spraggett) ~ $ gcc -E -dM -x c /dev/null | sort >/tmp/t1
> (martinrb@spraggett) ~ $ gcc -E -dD -x c /dev/null | sort >/tmp/t2
> (martinrb@spraggett) ~ $ diff /tmp/t[12]
> 0a1,4
>> # 1 "<built-in>"
>> # 1 "<command-line>"
>> # 1 "/dev/null"
>> # 1 "/dev/null"
> (martinrb@spraggett) ~ $ wc /tmp/t[12]
> 111  340 3482 /tmp/t1
> 115  352 3552 /tmp/t2
> 226  692 7034 total
> (martinrb@spraggett) ~ $ gcc --version
> gcc (GCC) 4.2.3 (Ubuntu 4.2.3-2ubuntu7)
>
>
> -- 
>           Summary: gcc -E -dD prints predefined macros, contrary to  
> docs
>           Product: gcc
>           Version: 4.2.3
>            Status: UNCONFIRMED
>          Severity: normal
>          Priority: P3
>         Component: preprocessor
>        AssignedTo: unassigned at gcc dot gnu dot org
>        ReportedBy: martinrb at google dot com
>  GCC host triplet: x86_64-linux-gnu
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37549
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37549



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