Re: RFA: complex numbers in c-valprint.c

[Daniel Jacobowitz <drow@mvista.com>]

On Sun, Feb 03, 2002 at 05:44:50PM -0500, Jim Blandy wrote:
> 
> Daniel Jacobowitz <drow@mvista.com> writes:
> > This patch fixes half of gdb/320.  The other half is a bug in GCC 3.x, that
> > I just CC'd gdb@ about.
> > 
> > Is this OK to commit?  Does anyone have a preference for {0, 0} vs. { re =
> > 0, im = 0}?  I used the former.
> 
> {0, 0} looks to me like GDB's syntax for array literals.  In ISO C
> programs, don't you just write complex literals as x+I*y?  What's wrong
> with GDB printing that?
> 
> If you say, "It shouldn't be an expression!", then I'll just say, "We
> already print negative numbers as an expression!"  Lexically speaking,
> C integer literals can't have a sign.  `-3' is an application of the
> prefix operator `-' to the literal `3'.  Since the spec promises that
> the compiler will fold constant expressions, you don't need a
> dedicated syntax for negative numbers.  I assume the same thinking is
> behind the lack of any syntactic support for complex literals.

x + y * I, I think.  That's nice; I didn't realize C99 and <complex.h>
supported ``I''.

OK with that syntax change?

> (The bikeshed should be a nice yellow-green, I think.)

...

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer