On Mon, Sep 9, 2019 at 8:09 PM Mateus Carmo Martins de Freitas Barbosa <mateus.carmo.barb...@usp.br> wrote: > > There's an ongoing discussion on the rustc forum > (<https://users.rust-lang.org/t/call-for-help-implementing-an-independent-rust-frontend-for-gcc/32163>) > on implementing a GCC front-end for the Rust compiler, and the issue > of whether GIMPLE is stable was brought up. Namely, if a compiler > front-end were to output GIMPLE directly, how often (if at all) would > its codebase have to be changed to due to breaking changes from GCC? > > I did find this reply > <https://gcc.gnu.org/ml/gcc/2011-05/msg00313.html> which says: > > >> ?^ It looks like GIMPLE is expected to change per version of gcc. Is there > >> a time in >> the future when GIMPLE will be pretty stable? > > > > "Pretty stable" won't be enough, and I don't see us arriving there at > > the moment. > > But this is fairly old (2011) so it seemed reasonable to ask if this > is still the case.
GIMPLE is fairly stable but not 100% stable. The way the Go frontend handles this is that the file that converts between the Go frontend IR and GIMPLE is part of the GCC tree (gcc/go/go-gcc.cc). This file is then routinely updated whenever three is a tree-wide GIMPLE change. With that approach I very rarely have to change the GIMPLE generation code myself. Ian
