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| author | Andrew Cann <shum@canndrew.org> | 2016-08-02 19:56:33 +0800 |
|---|---|---|
| committer | Andrew Cann <shum@canndrew.org> | 2016-08-13 21:37:09 +0800 |
| commit | 36393416850acf560554411a04b0098fcf3debd9 (patch) | |
| tree | 863190ef6b774270d24aefc7d5390033bbb7167f | |
| parent | 54c72d8f98a5693ab04c71942d07fb777e17a951 (diff) | |
| download | rust-36393416850acf560554411a04b0098fcf3debd9.tar.gz rust-36393416850acf560554411a04b0098fcf3debd9.zip | |
Default diverging types based on feature gate.
Default to either `!` or `()` depending on whether feature(never_type) is on or not.
| -rw-r--r-- | src/librustc/ty/context.rs | 8 | ||||
| -rw-r--r-- | src/librustc_typeck/check/mod.rs | 8 |
2 files changed, 12 insertions, 4 deletions
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs index 8ca02eaabe6..4056fb01aa2 100644 --- a/src/librustc/ty/context.rs +++ b/src/librustc/ty/context.rs @@ -1266,6 +1266,14 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> { self.mk_tup(Vec::new()) } + pub fn mk_diverging_default(self) -> Ty<'tcx> { + if self.sess.features.borrow().never_type { + self.types.never + } else { + self.mk_nil() + } + } + pub fn mk_bool(self) -> Ty<'tcx> { self.mk_ty(TyBool) } diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs index 6ad7c5a8477..60935d47413 100644 --- a/src/librustc_typeck/check/mod.rs +++ b/src/librustc_typeck/check/mod.rs @@ -1977,7 +1977,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> { if self.type_var_diverges(resolved) { debug!("default_type_parameters: defaulting `{:?}` to `!` because it diverges", resolved); - self.demand_eqtype(syntax_pos::DUMMY_SP, *ty, self.tcx.types.never); + self.demand_eqtype(syntax_pos::DUMMY_SP, *ty, self.tcx.mk_diverging_default()); } else { match self.type_is_unconstrained_numeric(resolved) { UnconstrainedInt => { @@ -2051,7 +2051,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> { for ty in &unsolved_variables { let resolved = self.resolve_type_vars_if_possible(ty); if self.type_var_diverges(resolved) { - self.demand_eqtype(syntax_pos::DUMMY_SP, *ty, self.tcx.types.never); + self.demand_eqtype(syntax_pos::DUMMY_SP, *ty, self.tcx.mk_diverging_default()); } else { match self.type_is_unconstrained_numeric(resolved) { UnconstrainedInt | UnconstrainedFloat => { @@ -2109,7 +2109,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> { let _ = self.commit_if_ok(|_: &infer::CombinedSnapshot| { for ty in &unbound_tyvars { if self.type_var_diverges(ty) { - self.demand_eqtype(syntax_pos::DUMMY_SP, *ty, self.tcx.types.never); + self.demand_eqtype(syntax_pos::DUMMY_SP, *ty, self.tcx.mk_diverging_default()); } else { match self.type_is_unconstrained_numeric(ty) { UnconstrainedInt => { @@ -2205,7 +2205,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> { // reporting for more then one conflict. for ty in &unbound_tyvars { if self.type_var_diverges(ty) { - self.demand_eqtype(syntax_pos::DUMMY_SP, *ty, self.tcx.types.never); + self.demand_eqtype(syntax_pos::DUMMY_SP, *ty, self.tcx.mk_diverging_default()); } else { match self.type_is_unconstrained_numeric(ty) { UnconstrainedInt => { |