Is there a NULL pointer to functions?

[der Mouse]

In article <4429 at inews.intel.com>, bhoughto at pima.intel.com (Blair P. Houghton) writes:

[stuff about comparing pointer-to-function to NULL]

> [ANSI X3.159-1989, sec. 3.2.2.3, says]

> 	"An integral constant expression with the value 0, or such an
> 	 expression cast to type void *, is called a null pointer
> 	 constant.  If a null pointer constant is assigned to or
> 	 compared for equality to a pointer, the constant is converted
> 	 to a pointer of that type.  Such a pointer, called a null
> 	 pointer, is guaranteed to compare unequal to a pointer to any
> 	 object or function."

> This doesn't abrogate the necessity that comparisons involve
> compatible types, however, nor that bare constants take the type of
> the object to which they are assigned or compared.

But I believe it *does* require that comparing a function pointer to
(void *)0 convert the null pointer to the appropriate function pointer
type, which the compiler in the original posting was not doing.  (Or at
least was not being silent about.)

					der Mouse

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