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>I think I'm getting overly agressive optimization. > >When I compile this function: > extern unsigned long ptr; > > int func(void) > { > unsigned long val = (unsigned long)&ptr; > > if (val == 0) { > return 1; > } else { > return 0; > } > } > >with any optimization level > 0, I get this: > func: > clr.l %d0 > rts > >It looks like it's assuming a pointer can't be NULL. I think the compiler is assuming that the *address* of a pointer can't be NULL, not the value. If your code was: > unsigned long val = (unsigned long)ptr; then I think the compiler would load the *value* of ptr instead of the *address* of ptr and then test the *value* for NULL, not test its *address* for NULL. I don't think there is any case where an *address* of a pointer(not its value) can be NULL? -- Peter Barada peter@the-baradas.com ------ Want more information? See the CrossGCC FAQ, http://www.objsw.com/CrossGCC/ Want to unsubscribe? Send a note to crossgcc-unsubscribe@sources.redhat.com
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