On Wed, 18 Feb 2015, Josh Poimboeuf wrote: > On Wed, Feb 18, 2015 at 01:42:56PM +0100, Miroslav Benes wrote: > > On Tue, 17 Feb 2015, Josh Poimboeuf wrote: > > > > > On Tue, Feb 17, 2015 at 04:48:39PM +0100, Miroslav Benes wrote: > > > > On Tue, 17 Feb 2015, Josh Poimboeuf wrote: > > > > > > > > > On Mon, Feb 16, 2015 at 03:19:10PM +0100, Miroslav Benes wrote: > > > > > > > > > and externs for functions are redundant. > > > > > > > > > > I agree, but it seems to be the norm in Linux. I have no idea why. I'm > > > > > just following the existing convention. > > > > > > > > Yes, I know. It seems that each author does it differently. You can find > > > > both forms even in one header file in the kernel. There is no functional > > > > difference AFAIK (it is not the case for variables of course). So as long > > > > as we are consistent I do not care. And since we have externs already in > > > > livepatch.h... you can scratch this remark if you want to :) > > > > > > Ok. If there are no objections, let's stick with our existing > > > nonsensical convention for now :-) > > > > So I was thinking about it again and we should not use bad patterns in our > > code from the beginning. Externs do not make sense so let's get rid of > > them everywhere (i.e. in the consistency model and also in livepatch.h). > > > > The C specification talks about extern in context of internal and external > > linkages or in context of inline functions but it does not make any sense > > to me. Could you look at the specification and tell me if it makes any > > sense to you, please? > > Relevant parts from C11: > > For an identifier declared with the storage-class specifier extern in a > scope in which a prior declaration of that identifier is visible, if the > prior declaration specifies internal or external linkage, the linkage of > the identifier at the later declaration is the same as the linkage > specified at the prior declaration. If no prior declaration is visible, > or if the prior declaration specifies no linkage, then the identifier > has external linkage. > > If the declaration of an identifier for a function has no storage-class > specifier, its linkage is determined exactly as if it were declared with > the storage-class specifier extern .If the declaration of an identifier > for an object has file scope and no storage-class specifier, its linkage > is external. > > Sounds to me like "extern" is redundant for functions. I'm fine with > removing it. Care to work up a patch for livepatch.h? Agreed. I'll do that. Thanks. Miroslav -- To unsubscribe from this list: send the line "unsubscribe live-patching" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
