🚀 go-pugleaf

In <3vo921$n4a@pheidippides.axion.bt.co.uk> thomasgd@boat.bt.com (Greg Thomas) writes:

>Hi,
>
>I'm trying to porting some code to Alpha/DEC 'C' from VAX/VAX 'C'. We have, 
>however, hit a problem with the <errno.h> include file. It #defines it to be 
>(*cma$tis_errno_get_addr()). The trouble is, we have number of structures that 
>have an errno as an element. Of course, this gets expanded to the above 
>function, and so it won't compile. ie ...
>
You got precisely what you deserved.

>Now whilst I can change all our code to not refer to errno in this structure, 
>I feel that the DEC 'C' errno.h does not have correct behaviour in it. Is the 
>DEC 'C' compiler in error (my K&R 2nd Ed does refer to errno as an integer, 
>but that's all), or am I not allowed to do this?

It's all your fault.  Here's the relevant part of the standard:

    4.1.3 Errors <errno.h>

    The header <errno.h> defines several macros, all relating to the
    reporting of error conditions.

       The macros are 
           ^^^^^^
	     EDOM
	     ERANGE

    which expand to distinct nonzero integral constant expressions; and 

	     errno

    which expands to a modifiable lvalue that has type int...
          ^^^^^^^

(*cma$tis_errno_get_addr()) looks like a modifiable lvalue, so the 
implementation is correct (the cma$tis_errno_get_addr symbol is
definitely not in the user's namespace).

Time to fix your code.

Dan
--
Dan Pop
CERN, CN Division
Email: Dan.Pop@mail.cern.ch 
Mail:  CERN - PPE, Bat. 31 R-004, CH-1211 Geneve 23, Switzerland