Is this really the best we can do?

ecstatic-morse · ecstatic-morse · commit ef49daa4238e · 2020-10-02T10:13:52.000-07:00
diff --git a/compiler/rustc_mir_build/src/build/mod.rs b/compiler/rustc_mir_build/src/build/mod.rs
@@ -29,7 +29,13 @@ crate fn mir_built<'tcx>(
         return tcx.mir_built(def);
     }
 
-    tcx.alloc_steal_mir(mir_build(tcx, def))
+    let mut body = mir_build(tcx, def);
+    if def.const_param_did.is_some() {
+        assert!(matches!(body.source.instance, ty::InstanceDef::Item(_)));
+        body.source = MirSource::from_instance(ty::InstanceDef::Item(def.to_global()));
+    }
+
+    tcx.alloc_steal_mir(body)
 }
 
 /// Construct the MIR for a given `DefId`.

Original file line number	Diff line number	Diff line change
`@@ -29,7 +29,13 @@ crate fn mir_built<'tcx>(`
`29`	`29`	`return tcx.mir_built(def);`
`30`	`30`	`}`
`31`	`31`
`32`		`- tcx.alloc_steal_mir(mir_build(tcx, def))`
	`32`	`+ let mut body = mir_build(tcx, def);`
	`33`	`+ if def.const_param_did.is_some() {`
	`34`	`+ assert!(matches!(body.source.instance, ty::InstanceDef::Item(_)));`
	`35`	`+ body.source = MirSource::from_instance(ty::InstanceDef::Item(def.to_global()));`
	`36`	`+ }`
	`37`	`+`
	`38`	`+ tcx.alloc_steal_mir(body)`
`33`	`39`	`}`
`34`	`40`
`35`	`41`	/// Construct the MIR for a given `DefId`.