diff options
| -rw-r--r-- | compiler/rustc_mir_build/src/build/matches/mod.rs | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs index 68244136d1a..350b00db7fd 100644 --- a/compiler/rustc_mir_build/src/build/matches/mod.rs +++ b/compiler/rustc_mir_build/src/build/matches/mod.rs @@ -358,8 +358,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { where 'a: 'pat, { - // Assemble a list of candidates: there is one candidate per pattern, - // which means there may be more than one candidate *per arm*. + // Assemble the initial list of candidates. These top-level candidates + // are 1:1 with the original match arms, but other parts of match + // lowering also introduce subcandidates (for subpatterns), and will + // also flatten candidates in some cases. So in general a list of + // candidates does _not_ necessarily correspond to a list of arms. arms.iter() .copied() .map(|arm| { |