On Wed, Nov 20, 2019 at 2:13 PM Denton Liu <liu.denton@xxxxxxxxx> wrote:
> On Wed, Nov 20, 2019 at 01:26:04PM +0900, Junio C Hamano wrote:
> > Denton Liu <liu.denton@xxxxxxxxx> writes:
> > > +#include "argv-array.h"
> > >
> > > int show_range_diff(const char *range1, const char *range2,
> > > int creation_factor, int dual_color,
> > > - struct diff_options *diffopt);
> > > + struct diff_options *diffopt,
> > > + struct argv_array *other_arg);
> >
> > I thought a mere use of "pointer to a struct" did not have to bring
> > the definition of the struct into the picture? In other words,
> > wouldn't it be fine to leave the other_arg a pointer to an opaque
> > structure by not including "argv-array.h" in this file?
>
> Without including "argv-array.h", we get the following hdr-check error:
>
> $ make range-diff.hco
> In file included from range-diff.hcc:2:
> ./range-diff.h:16:14: error: declaration of 'struct argv_array' will not be visible outside of this function [-Werror,-Wvisibility]
> struct argv_array *other_arg);
Did you forward-declare 'argv_array' in range-diff.h? That is, rather than:
#include "argv-array.h"
instead say:
struct argv_array;
which tells the compiler that the type exists, thus allowing you to
deal with pointers to the struct, as long as you don't try to access
any of the struct's members in code which has seen only the forward
declaration. You would still need to #include "argv-array.h" in
range-diff.c, though.
