When you have done enough C++ you don't need to fire up compiler explorer, you just use local variables to avoid aliasing pessimisations.<p>I also wrote about this a while ago: <a href="https://forwardscattering.org/post/51" rel="nofollow">https://forwardscattering.org/post/51</a>
For a real world example of how this can affect code check out this commit I made in mesa: <a href="https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20877/diffs?commit_id=4b8dfaae89eedd54f7f9881adc8712d99ff30a60" rel="nofollow">https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20...</a>
Aliasing is no joke and currently the only reason why some arithmetic intensive code-bases still prefer Fortran even nowadays.<p>While it is possible to remove most aliasing performance issues in a C or C++ codebase, it is <i>a pain</i> to do it properly.
Aliasing can be a problem in Fortran too.<p>Decades ago I was a Fortran developer and encountered a very odd bug in which the wrong values were being calculated. After a lot of investigation I tracked it down to a subroutine call in which a hard-coded zero was being passed as an argument. It turned out that in the body of that subroutine the value 4 was being assigned to that parameter for some reason. The side effect was that the value of zero because 4 for the rest of the program execution because Fortran aliases all parameters since it passes by descriptor (or at least DEC FORTRAN IV did so on RSX/11). As you can imagine, hilarity ensued.
The whole series is excellent and as a non regular user of assembly I learned a ton.
I wonder how much potential optimisation there is if we entirely drop pointer nonsense.
For a system programming language the right solution is to properly track aliasing information in the type system as done in Rust.<p>Aliasing issues is just yet another instance of C/C++ inferiority holding the industry back. C could've learnt from Fortran, but we ended up with the language we have...
Are you talking about dropping pointers as a programmer-facing programming language concept (in which case you might find Hylo and similar languages interesting), or dropping pointers from <i>everything</i> - programming languages, their implementations, compilers, etc. (in which case I'm not sure that's even possible)?