Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!pt.cs.cmu.edu!pt!dld From: dld@F.GP.CS.CMU.EDU (David Detlefs) Newsgroups: comp.lang.c++ Subject: Re: is type-safe linkage safe? Message-ID: Date: 27 Oct 89 21:05:50 GMT Organization: CMU CS Department Lines: 40 Isn't it true that there is a sense in which the C++ 2.0 "type-safe linkage" mechanism is not type-safe, because they do not include the return types? If I do a.c: ---------------------------------------------------------------------- int foo() { return 7; }; ---------------------------------------------------------------------- b.c: ---------------------------------------------------------------------- #include #include extern char* foo(); void main() { cout << strlen(foo()) << "\n"; } ---------------------------------------------------------------------- and make a.o and b.o, won't the foo's in both files end up with the same "mangled" names, allowing everything to link without complaint. I just tried this in g++ and it doesn't complain -- the resulting executable produces the output '0' (on a vax). I expect the result would be the same in AT&T 2.0. The only reason I can think of for not including the return type (and thus detecting type errors like the one above) in the mangled name is concern about the length of the names. Are there other reasons that I'm missing? -- Dave Detlefs Any correlation between my employer's opinion Carnegie-Mellon CS and my own is statistical rather than causal, dld@cs.cmu.edu except in those cases where I have helped to form my employer's opinion. (Null disclaimer.)