alt Hacker Newsi know in the embedded space this would be invaluable. compile time contracts, or compile time abstract base class would enable compile time resolution of virtuals. so then i can do compile-time polymorphism and c++ is suddenly really attractive in the sub 64k memory space. Maybe -flto does this idk. But all the pieces are there.
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> compile time abstract base class would enable compile time resolution of virtuals. so then i can do compile-time polymorphism
What's wrong with static polymorphism that have been around for at least 31 years? (1995 per [1]). Also know as CRTP [2] Apart, of course, from ugly verbose compilation errors...
And now c++23 "deducing `this`" [3,4] modern replacement which is supposed to improve compilation time and remove the verbose errors.
[1] https://www.artima.com/articles/the-most-important-c-non-boo...
[2] https://en.cppreference.com/cpp/language/crtp
[3] https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2021/p08...
[4] https://devblogs.microsoft.com/cppblog/cpp23-deducing-this/
Yeah, I heard spark was used on a small component in the nvidia gpu firmware so others seemingly agree. I'm mainly in the user mode driver space so my ideas have been around having a kernel mode driver that (assuming a correctly functioning pc) can't crash and user mode drivers that can't be exploited (at least in the rop chain sense). I'm kind of picking ideas from other languages that I like zig's error handling, ada's contracts, rust's lifetimes (hopefully soon to be replaced with more contracts instead), and things like how you can use "gas" in lean to prove a loops will terminate. I'm mainly building it up with AI right now for experimentation, but I also can't really trust it to be correct either because of using AI. Once I settle on the syntax more and pump out a lot more tests, I'm probably going to rewrite the compiler by hand (hopefully in the custom language itself.)
How would this allow compile-time resolution of virtuals that was not possible before?
Gcc can already do link-time devirtualization in some cases.
You might want to take a look at Real-time C++: Efficient Object-oriented and Template Microcontroller Programming by Christopher Kormanyos for some ideas.
Also take a look at David Crocker's Escher Technologies "Escher C Verifier and Escher C++ Verifier" (https://www.eschertech.com/products/ecv.php) and articles on "Verified Design-By-Contract" etc. linked to in my comment chain here - https://news.ycombinator.com/item?id=48544022
Contracts are written such that the compiler can diagnose a detected violation if it wants to. However most contracts realistically need whole program analysis to diagnose and no compiler can do that - you want a separate static analysis for that. (this doesn't exist, but there is hope people start writing those)