diff --git a/mk2rbc/expr.go b/mk2rbc/expr.go
index 07f7ca189..dc16d1d2f 100644
--- a/mk2rbc/expr.go
+++ b/mk2rbc/expr.go
@@ -595,6 +595,7 @@ func (cx *callExpr) transform(transformer func(expr starlarkExpr) starlarkExpr)
 	for i, arg := range cx.args {
 		argsCopy[i] = arg.transform(transformer)
 	}
+	cx.args = argsCopy
 	if replacement := transformer(cx); replacement != nil {
 		return replacement
 	} else {
diff --git a/mk2rbc/mk2rbc_test.go b/mk2rbc/mk2rbc_test.go
index 447f658ee..554e99eb9 100644
--- a/mk2rbc/mk2rbc_test.go
+++ b/mk2rbc/mk2rbc_test.go
@@ -1228,6 +1228,9 @@ BOOT_KERNEL_MODULES_LIST := foo.ko
 BOOT_KERNEL_MODULES_LIST += bar.ko
 BOOT_KERNEL_MODULES_FILTER_2 := $(foreach m,$(BOOT_KERNEL_MODULES_LIST),%/$(m))
 
+FOREACH_WITH_IF := $(foreach module,\
+  $(BOOT_KERNEL_MODULES_LIST),\
+  $(if $(filter $(module),foo.ko),,$(error module "$(module)" has an error!)))
 `,
 		expected: `load("//build/make/core:product_config.rbc", "rblf")
 
@@ -1238,6 +1241,7 @@ def init(g, handle):
   g["BOOT_KERNEL_MODULES_LIST"] = ["foo.ko"]
   g["BOOT_KERNEL_MODULES_LIST"] += ["bar.ko"]
   g["BOOT_KERNEL_MODULES_FILTER_2"] = ["%%/%s" % m for m in g["BOOT_KERNEL_MODULES_LIST"]]
+  g["FOREACH_WITH_IF"] = [("" if rblf.filter(module, "foo.ko") else rblf.mkerror("product.mk", "module \"%s\" has an error!" % module)) for module in g["BOOT_KERNEL_MODULES_LIST"]]
 `,
 	},
 	{