diff --git a/Makefile b/Makefile
index 38fa65a1..d2c29ab4 100644
--- a/Makefile
+++ b/Makefile
@@ -584,8 +584,7 @@ DATABYTEID_EXPECTED_MIN = 911
 # this list rather than silently widening coverage.  Tracked with the #59
 # divergence family.
 DATABYTEID_DIVERGED = r76_typeeq_fn_diff_arity r76_typeeq_fn_diff_param_type \
-	  r76_typeeq_fn_io_vtable_shape r76_typeeq_fn_variadic_vs_fixed \
-	  r940_str_forrange_arg
+	  r76_typeeq_fn_io_vtable_shape r76_typeeq_fn_variadic_vs_fixed
 $(if $(DATABYTEID_FILES),,$(error test-byteid: empty data corpus))
 test-data-byteid: $(BIN)/ww $(BIN)/w6c $(BIN)/w6c_ww
 	@work=$$(mktemp -d "$(CURDIR)/$(DATABYTEID_DIR).XXXXXX") || exit 1; \
diff --git a/selfhost/cmd/wcc/check.ww b/selfhost/cmd/wcc/check.ww
index cb958f78..776f639a 100644
--- a/selfhost/cmd/wcc/check.ww
+++ b/selfhost/cmd/wcc/check.ww
@@ -584,9 +584,7 @@ fn resolvewalk(c: *checker, n: *syntax.node) void = {
 				// types it: check.c N_FORRANGE scope_define(...,
 				// elem, ...)). Synthetic N_LET binder whose .lhs
 				// is the element tnode — the stamptuplebinds
-				// `b.lhs = et` idiom. A str scrutinee keeps the
-				// old decl: cgen synthesises the u8 elem there
-				// and no dot applies to a u8 binding.
+				// `b.lhs = et` idiom.
 				let et: *syntax.node = nil;
 				let it: *syntax.node = exprtype(c, n.lhs, nil);
 				// #80 (F2a batch-4 c4): an alias-typed iterable
@@ -599,6 +597,16 @@ fn resolvewalk(c: *checker, n: *syntax.node) void = {
 				if (it != nil) {
 					if (it.kind == syntax.nkind.N_TSLICE) { et = it.lhs; };
 					if (it.kind == syntax.nkind.N_TARRAY) { et = it.lhs; };
+					// A str binding is u8 (cstage check.c: elem =
+					// ty_u8). The old N_FORRANGE fallback decl made
+					// exprtype stamp the binding str, so call-arg
+					// marshaling pushed the 3-word str ABI for a
+					// 1-word scalar.
+					if (it.kind == syntax.nkind.N_TNAME) {
+						if (syntax.streq(it.str, "str")) {
+							et = mktname(c, "u8");
+						};
+					};
 				};
 				if (et != nil) {
 					let bn: *syntax.node = syntax.newnode(syntax.nkind.N_LET, n.file, n.line, n.col);