Andres Freund <andres@2ndquadrant.com> writes:
> On 2013-06-14 11:59:04 -0400, Tom Lane wrote:
>> Ah, you are right, I forgot the #ifndef CHECKSUM_IMPL_H dance. Will fix
>> in a bit.
> That won't help against errors if it's included in two different
> files/translation units though.
Good point, but there's not any real reason to do that --- only
checksum.h should ever be #include'd in more than one file. Any program
using this stuff is expected to #include checksum_impl.h in exactly one
place. So maybe it's fine as-is.
> E.g. in rmgrlist.h we have the following comment:
> /* there is deliberately not an #ifndef RMGRLIST_H here */
> and I think the reasoning behind that comment applies here as well.
Well, that's a different case: there, and also in kwlist.h, there's an
idea that it could actually be useful to #include the file more than
once, redefining the PG_RMGR() macro each time. There's no such use
case that I can see for checksum_impl.h.
regards, tom lane