On Tue, Aug 02, 2005 at 09:57:39AM -0400, Diego Novillo wrote: > On Tue, Aug 02, 2005 at 09:39:56AM -0400, Daniel Jacobowitz wrote: > > > Then the alias analyzer's broken. > > > Broken? I'm saying that we currently get this right. I don't > know what position are you arguing. Sorry, my mistake. I'd forgotten that Ian said we got this right in 4.1. > This code does builds an address location out of an arbitrary integer: > > unsigned int D.1142_8 = *ptr_1; > struct cons *D.1143_9 = (struct cons *) D.1142_8; > ptr_10 = &D.1143_9->cdr; > > Does the language allow the creation of address locations out of > arbitrary integer values? Is the dereference of such an > address a defined operation? If so, then it's simply a matter of > recognizing this situation when computing points-anywhere > attributes. Yes, it does - well, it's implementation defined, but GCC has long chosen the natural interpretation. C99 6.3.2.3, paragraph 5. This is no different from that classic example, a pointer which escapes via printf/scanf. -- Daniel Jacobowitz CodeSourcery, LLC
