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| author | Niko Matsakis <niko@alum.mit.edu> | 2016-03-18 18:40:22 -0400 |
|---|---|---|
| committer | Niko Matsakis <niko@alum.mit.edu> | 2016-03-18 18:40:22 -0400 |
| commit | 43aed96d0da2cfa6e5da3058c107f3de4a3c009b (patch) | |
| tree | 2a5bd82ddf970e891b192c0c89ebfa01f0e0d772 /src | |
| parent | 25988b645dfa5f56d35a4428e8c5e8c67706aaf4 (diff) | |
| download | rust-43aed96d0da2cfa6e5da3058c107f3de4a3c009b.tar.gz rust-43aed96d0da2cfa6e5da3058c107f3de4a3c009b.zip | |
add assertion and comment about mutability
Diffstat (limited to 'src')
| -rw-r--r-- | src/librustc_typeck/check/coercion.rs | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/src/librustc_typeck/check/coercion.rs b/src/librustc_typeck/check/coercion.rs index 164503980cd..bb27333025e 100644 --- a/src/librustc_typeck/check/coercion.rs +++ b/src/librustc_typeck/check/coercion.rs @@ -367,6 +367,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> { // `self.x` both have `&mut `type would be a move of // `self.x`, but we auto-coerce it to `foo(&mut *self.x)`, // which is a borrow. + assert_eq!(mt_b.mutbl, hir::MutImmutable); // can only coerce &T -> &U return self.identity(ty); } let r_borrow = match ty.sty { |