Path: utzoo!attcan!uunet!husc6!bbn!rochester!cornell!aitken From: aitken@svax.cs.cornell.edu (William Aitken) Newsgroups: comp.lang.c Subject: Possible bug in the SUN C compiler Message-ID: <18266@cornell.UUCP> Date: 13 Jun 88 19:34:27 GMT Sender: nobody@cornell.UUCP Reply-To: aitken@cs.cornell.edu (William Aitken) Followup-To: comp.lang.c Distribution: comp Organization: Cornell Univ. CS Dept, Ithaca NY Lines: 36 Yesterday, I was compiling some code and had a piece of code that I didn't think could possibly compile compile without error. In fact, lint didn't even complain. The problem is that the compiler allows one to use variables of struct type as switch selectors. This can't be right. Can it??? The reason I don't think its right is that there is no way to specify the case labels -- after all there are no anonymous structure constants in C. Furthermore, some quick investigation suggests that what the compiler does is to select on the first element of the structure. Below is a code fragment which compiles without error on SUN OS version 3.5. (incidentally Mt. Xinu 4.3 complains about it) struct splat { int foo_foo; int foo_bar; } foo; unsigned int convfoo(bar) struct splat bar; { switch (bar) { case 1:break; default:foo = bar;break; } return 0; } The question is this a bug, or this behavior mandated by K&R or the proposed ANSI standard. If the latter, why is such a kludge mandated? --- Bill. William E. Aitken(607)257-2542(h) {uw-beaver,ihnp4,vax135,decvax}!cornell!aitken (607)255-4222(o) aitken@crnlcs.BITNET 700 Warren Rd. #20-2A, Ithaca, NY 42 26'30" N 76 29'00" W 4148 Upson Hall