On 05/08/16 23:26, Johannes Sixt wrote: > When refs.c is being compiled, the only mention of enum iterator_selection is in this piece of code pulled in from refs-internal.h (have a look at the preprocessed code): > > typedef enum iterator_selection ref_iterator_select_fn( > struct ref_iterator *iter0, struct ref_iterator *iter1, > void *cb_data); > > This looks like a forward declarations of an enumeration type name, something that I thought is illegal in C. Am I wrong? (That may well be the case, my C-foo is quite rusty.) At this point 'enum iterator_selection' is an incomplete type and may be used when the size of the object is not required. It is not needed, for example, when a typedef name is being declared as a pointer to, or as a function returning such a type. However, such a type must be complete before such a function is called or defined. > My compiler does not complain (it's gcc 4.8), but I thought I mention it before someone with a pickier compiler stumbles over it... So, I think this is correct. Having said that, I would rather the 'enum iterator_selection' be defined before this declaration. One solution could be to #include "iterator.h" prior to _all_ #include "refs/refs-internal.h" in all compilation units (Note it is in the opposite order in refs/iterator.c). Alternatively, you could put the #include "../iterator.h" into refs/refs-internal.h directly (some people would object to this). ATB, Ramsay Jones -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html