> On Mar 7, 2017, at 8:45 AM, bigpig <bigpig1...@gmail.com> wrote: > > if there is C++ compiler and use C linkage,but if there isn’t C++ compiler > then use what?
Then it’s a C compiler, which obviously uses C linkage. > And what is the reason of using this way in code? To make sure that the functions declared inside can be called from C or C++ code. If this “extern” declaration weren’t there, a C++ compiler would treat those functions as having C++ linkage, which means their names will be “mangled” to include information about their parameter types. That would cause a link error, because the program is referring to the function by a mangled name while the actual function has a plain C name. —Jens _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
