Re: Feature request - a macro defined for GCC

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Author: Andreas Schwab
Date:  
To: gcc
Subject: Re: Feature request - a macro defined for GCC
Vincent Lefevre <vincent+gcc@???> writes:

> On 2008-07-02 00:12:33 +0000, Joseph S. Myers wrote:
>> This internal binary no longer exists. Instead, there is a "cpp"
>> binary installed in the user binary directory, which calls the "cc1"
>> binary to do the same preprocessing as it does when compiling; that
>> is, it has the same effect as "gcc -E".
>
> Not exactly:
>
> vin% cpp -dM /dev/null | wc -l
> 128
> vin% gcc -E -dM /dev/null | wc -l
> gcc.real: /dev/null: linker input file unused because linking not done
> 0
>
> Is it a bug of "gcc -E"?


You need to tell gcc that /dev/null is a C file, since it does not have
a recognized extension.

$ gcc -E -dM -xc /dev/null | wc -l
120

Andreas.

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Andreas Schwab, SuSE Labs, schwab@???
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