Generating Function Prototypes

Simon Marlow simonmar at
Mon Jul 8 07:22:21 EDT 2002

> >Sure, it's a problem, a bug in GHC, whatever.  But I don't see a way
> >around it!  We can't just generate prototypes because they might
> >conflict with prototypes already in scope.
> I see the problem now.
> This seems to compile (with a warning):
>     typedef long long HsInt64;
>     int foo (int); // annoying decl we want to ignore
>     // foo :: Int64 -> IO Int64
>     inline HsInt64 call_foo (HsInt64 x)
>         {
>         static HsInt64 foo(HsInt64);
>         return foo(x);
>         };
> I haven't actually tested it, but it may be a solution.

Strange; gcc doesn't generate an error for the local prototype for
foo(), although it does if you remove the 'static'.  My copy of the C99
standard has this to say:

       [#7]  If,  within  a  translation  unit, the same identifier
       appears  with  both  internal  and  external  linkage,   the
       behavior is undefined.


       20)A  function  declaration  can  contain  the storage-class
          specifier static only if it is at file scope; see  6.7.1.

which I think means that you shouldn't do this.  GCC seems to be not
complying with C99 here.


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