2 files changed, 13 insertions, 5 deletions
diff --git a/compiler/rustc_mir_build/src/build/expr/into.rs b/compiler/rustc_mir_build/src/build/expr/into.rs
index a8f623dbe46..418042ea665 100644
--- a/compiler/rustc_mir_build/src/build/expr/into.rs
+++ b/compiler/rustc_mir_build/src/build/expr/into.rs
@@ -255,10 +255,15 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                         func: fun,
                         args,
                         cleanup: None,
-                        // FIXME(varkor): replace this with an uninhabitedness-based check.
-                        // This requires getting access to the current module to call
-                        // `tcx.is_ty_uninhabited_from`, which is currently tricky to do.
-                        destination: if expr.ty.is_never() {
+                        // The presence or absence of a return edge affects control-flow sensitive
+                        // MIR checks and ultimately whether code is accepted or not. We can only
+                        // omit the return edge if a return type is visibly uninhabited to a module
+                        // that makes the call.
+                        destination: if this.tcx.is_ty_uninhabited_from(
+                            this.parent_module,
+                            expr.ty,
+                            this.param_env,
+                        ) {
                             None
                         } else {
                             Some((destination, success))
diff --git a/compiler/rustc_mir_build/src/build/mod.rs b/compiler/rustc_mir_build/src/build/mod.rs
index ab3dc8f020c..c4db2b32786 100644
--- a/compiler/rustc_mir_build/src/build/mod.rs
+++ b/compiler/rustc_mir_build/src/build/mod.rs
@@ -350,6 +350,7 @@ struct Builder<'a, 'tcx> {
 
     def_id: DefId,
     hir_id: hir::HirId,
+    parent_module: DefId,
     check_overflow: bool,
     fn_span: Span,
     arg_count: usize,
@@ -807,15 +808,17 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         );
 
         let lint_level = LintLevel::Explicit(hir_id);
+        let param_env = tcx.param_env(def.did);
         let mut builder = Builder {
             thir,
             tcx,
             infcx,
             typeck_results: tcx.typeck_opt_const_arg(def),
             region_scope_tree: tcx.region_scope_tree(def.did),
-            param_env: tcx.param_env(def.did),
+            param_env,
             def_id: def.did.to_def_id(),
             hir_id,
+            parent_module: tcx.parent_module(hir_id).to_def_id(),
             check_overflow,
             cfg: CFG { basic_blocks: IndexVec::new() },
             fn_span: span,