[gcc/devel/rust/master] Merge #1317

[gcc/devel/rust/master] Merge #1317

[Thomas Schwinge]

https://gcc.gnu.org/g:c0f11672d760513256997f325da678016d13f677

commit c0f11672d760513256997f325da678016d13f677
Merge: b711799e3eb 5f3c8286b22
Author: bors[bot] <26634292+bors[bot]@users.noreply.github.com>
Date:   Fri Jun 17 16:11:19 2022 +0000

    Merge #1317
    
    1317: AST for const generic arguments/const application r=CohenArthur a=CohenArthur
    
    This commit adds a new type to the AST which contains const generic
    arguments. The `GenericArgs` structure now also keeps a vector of them,
    and the parser was modified accordingly. We need to handle these extra
    arguments in the various resolvers and type-checking phase.
    
    As pointed out before, const generic arguments are ambiguous at the AST
    level. Which is why this "sum type" contains a "Clear" variant when
    there is no ambiguity at all (`<5>`, `<{ 5 }>`, `<{ 5 + 15 }>` or
    `<{ N }>`) and an "Ambiguous" one if the value in question might be
    referring to a type argument (`<N>`) instead of a const generic
    argument.
    
    Co-authored-by: Arthur Cohen <arthur.cohen@embecosm.com>

Diff:

 gcc/rust/ast/rust-ast-full-test.cc |  14 +++
 gcc/rust/ast/rust-path.h           | 205 ++++++++++++++++++++++++++++---------
 gcc/rust/parse/rust-parse-impl.h   |  57 ++++++-----
 gcc/rust/parse/rust-parse.h        |   2 +-
 4 files changed, 205 insertions(+), 73 deletions(-)