[gcc/devel/rust/master] Merge #810

[gcc/devel/rust/master] Merge #810

[Thomas Schwinge]

https://gcc.gnu.org/g:0995184e26f81f8ba6872c3efb59f640a7fe7162

commit 0995184e26f81f8ba6872c3efb59f640a7fe7162
Merge: 63fc39600ce db832831ed1
Author: bors[bot] <26634292+bors[bot]@users.noreply.github.com>
Date:   Thu Nov 18 00:16:47 2021 +0000

    Merge #810
    
    810: Fix MethodCalls for covariant impl blocks r=philberty a=philberty
    
    I think we need to research more into how we probe for potential candidates
    for method calls. This fixes a few bugs going on in #808 one where the
    canonical path was empty and one where we fail to probe directly on the
    receiver of reference types to impl blocks but we must be able to also support
    that autoderef means that a receiver's root type might actually be the type we
    care about for example a reference to a generic type-parameter and we probe
    its bounds for candidates for example. Lets consult the rustc code and references on this.
    
    Fixes #808
    
    Co-authored-by: Philip Herron <philip.herron@embecosm.com>

Diff:

 gcc/rust/Make-lang.in                           |  1 +
 gcc/rust/resolve/rust-ast-resolve-type.h        |  3 ++
 gcc/rust/resolve/rust-ast-resolve.cc            | 38 +++++++++++++++----
 gcc/rust/typecheck/rust-hir-type-check-expr.h   | 29 ++++++++++++---
 gcc/rust/typecheck/rust-substitution-mapper.cc  | 49 +++++++++++++++++++++++++
 gcc/rust/typecheck/rust-substitution-mapper.h   |  8 +---
 gcc/rust/typecheck/rust-tyty-call.h             |  9 +++--
 gcc/rust/typecheck/rust-tyty.cc                 |  2 +
 gcc/testsuite/rust/compile/torture/issue-808.rs | 23 ++++++++++++
 9 files changed, 140 insertions(+), 22 deletions(-)