On Wednesday 29 March 2006 23:28, Tom Tromey wrote: > >>>>> "Duncan" == Duncan Sands <[EMAIL PROTECTED]> writes: > > Duncan> That still leaves the problem of how the Ada front-end tells the > Duncan> middle-end that a variable is known to be in a certain range. Due > Duncan> to the way the language works, the front-end often does know a useful > Duncan> range, helpful for optimisation. If using types with strange ranges > Duncan> is out, and ASSERT_EXPRs aren't appropriate, what is left? > > Yeah, there's got to be something. > > On irc today we were discussing handling 'this' in gcj. We can add an > attribute to the argument to mark it as non-null... but strangely > there doesn't seem to be a way to mark other local variables as > known-non-null -- a curious deficiency.
If the front-end was allowed to place ASSERT_EXPRs in the trees it passes to the middle-end, then you could place such assertions on the appropriate local variables and voila. Jeff claimed that this would cause serious problems for the copy propagation pass, but I don't see why. All the best, Duncan.
