[TUHS] reviving a bit of WWB

Steffen Nurpmeso steffen at sdaoden.eu
Tue Sep 22 06:48:48 AEST 2020


John Cowan wrote in
 <CAD2gp_SV19s6yHsdApn8Rfkgb3OZCVFdd++_MWTsX5b7c_Jbig at mail.gmail.com>:
 |The confusion (I dare not call it a flame war) is arising out of the
 |difference between an object with all bits zero and a 0 constant (or
 |equivalently 2*0 or 3-3 or what not).   0 in pointer context is always a
 |null pointer, but it may or may not be all-bits-zero.  0 in integer context
 |is, on any sane machine, all-bits-zero (on 1's-complement machines it may
 |also be all-bits-one).
 |
 |Personally, when I was programming in C I defined a macro #define
 |NULLPTR(t) ((t)0), so that I would write NULLPTR(char *) or NULLPTR(int *)
 |or whatever the Right Thing was.

And i think too that POSIX is about to define this explicitly in
the future (regarding all bits zero).

--steffen
|
|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)


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