* GCC 3.3.2: Some bug in the preprocessor?
@ 2004-02-12 20:29 Denis Zaitsev
2004-02-12 20:34 ` Zack Weinberg
0 siblings, 1 reply; 3+ messages in thread
From: Denis Zaitsev @ 2004-02-12 20:29 UTC (permalink / raw)
To: gcc, linux-gcc
Look, this defun returns 0, and this is correct:
tst()
{
#if (unsigned)0 > -1
return 1;
#else
return 0;
#endif
}
But this one returns 1, and this is incorrect:
tst()
{
#if 0 > (unsigned)-1
return 1;
#else
return 0;
#endif
}
What's wrong?
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: GCC 3.3.2: Some bug in the preprocessor?
2004-02-12 20:29 GCC 3.3.2: Some bug in the preprocessor? Denis Zaitsev
@ 2004-02-12 20:34 ` Zack Weinberg
2004-02-12 20:44 ` Denis Zaitsev
0 siblings, 1 reply; 3+ messages in thread
From: Zack Weinberg @ 2004-02-12 20:34 UTC (permalink / raw)
To: gcc; +Cc: linux-gcc
You cannot use casts in #if. Your conditionals are read as
#if (0)0 > -1
which produces a syntax error;
#if 0 > (0)-1
which evaluates as 0 > 0 - 1 which is true.
zw
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: GCC 3.3.2: Some bug in the preprocessor?
2004-02-12 20:34 ` Zack Weinberg
@ 2004-02-12 20:44 ` Denis Zaitsev
0 siblings, 0 replies; 3+ messages in thread
From: Denis Zaitsev @ 2004-02-12 20:44 UTC (permalink / raw)
To: Zack Weinberg; +Cc: gcc, linux-gcc
On Thu, Feb 12, 2004 at 12:34:04PM -0800, Zack Weinberg wrote:
>
> You cannot use casts in #if. Your conditionals are read as
>
> #if (0)0 > -1
>
> which produces a syntax error;
Oh, ok, thanks. I've missed the error message...
^ permalink raw reply [flat|nested] 3+ messages in thread
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2004-02-12 20:29 GCC 3.3.2: Some bug in the preprocessor? Denis Zaitsev
2004-02-12 20:34 ` Zack Weinberg
2004-02-12 20:44 ` Denis Zaitsev
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