diff --git a/cli/src/repl.rs b/cli/src/repl.rs
index 2a5548e8ee..5cb1285b9d 100644
--- a/cli/src/repl.rs
+++ b/cli/src/repl.rs
@@ -257,7 +257,9 @@ pub fn gen(src: &[u8], target: Triple, opt_level: OptLevel) -> Result<(String, S
         ident_ids: &mut ident_ids,
     };
 
-    let main_body = roc_mono::ir::Stmt::new(&mut mono_env, loc_expr.value, &mut procs);
+    let mut layout_cache = LayoutCache::default();
+    let main_body =
+        roc_mono::ir::Stmt::new(&mut mono_env, loc_expr.value, &mut procs, &mut layout_cache);
     let main_body =
         roc_mono::inc_dec::visit_declaration(mono_env.arena, mono_env.arena.alloc(main_body));
     let mut headers = {
diff --git a/compiler/gen/tests/helpers/eval.rs b/compiler/gen/tests/helpers/eval.rs
index 92ca7f7fd1..2f02e81df4 100644
--- a/compiler/gen/tests/helpers/eval.rs
+++ b/compiler/gen/tests/helpers/eval.rs
@@ -13,7 +13,7 @@ pub fn helper_without_uniqueness<'a>(
     use roc_gen::llvm::build::Scope;
     use roc_gen::llvm::build::{build_proc, build_proc_header};
     use roc_gen::llvm::convert::basic_type_from_layout;
-    use roc_mono::layout::Layout;
+    use roc_mono::layout::{Layout, LayoutCache};
 
     let target = target_lexicon::Triple::host();
     let ptr_bytes = target.pointer_width().unwrap().bytes() as u32;
@@ -105,7 +105,9 @@ pub fn helper_without_uniqueness<'a>(
         ident_ids: &mut ident_ids,
     };
 
-    let main_body = roc_mono::ir::Stmt::new(&mut mono_env, loc_expr.value, &mut procs);
+    let mut layout_cache = LayoutCache::default();
+    let main_body =
+        roc_mono::ir::Stmt::new(&mut mono_env, loc_expr.value, &mut procs, &mut layout_cache);
     let main_body =
         roc_mono::inc_dec::visit_declaration(mono_env.arena, mono_env.arena.alloc(main_body));
 
@@ -214,7 +216,7 @@ pub fn helper_with_uniqueness<'a>(
     use roc_gen::llvm::build::Scope;
     use roc_gen::llvm::build::{build_proc, build_proc_header};
     use roc_gen::llvm::convert::basic_type_from_layout;
-    use roc_mono::layout::Layout;
+    use roc_mono::layout::{Layout, LayoutCache};
 
     let target = target_lexicon::Triple::host();
     let ptr_bytes = target.pointer_width().unwrap().bytes() as u32;
@@ -296,7 +298,9 @@ pub fn helper_with_uniqueness<'a>(
         ident_ids: &mut ident_ids,
     };
 
-    let main_body = roc_mono::ir::Stmt::new(&mut mono_env, loc_expr.value, &mut procs);
+    let mut layout_cache = LayoutCache::default();
+    let main_body =
+        roc_mono::ir::Stmt::new(&mut mono_env, loc_expr.value, &mut procs, &mut layout_cache);
     let main_body =
         roc_mono::inc_dec::visit_declaration(mono_env.arena, mono_env.arena.alloc(main_body));
     let mut headers = {
diff --git a/compiler/mono/src/ir.rs b/compiler/mono/src/ir.rs
index 7c690b4af4..7b5c62aae6 100644
--- a/compiler/mono/src/ir.rs
+++ b/compiler/mono/src/ir.rs
@@ -625,11 +625,11 @@ impl<'a> Stmt<'a> {
         env: &mut Env<'a, '_>,
         can_expr: roc_can::expr::Expr,
         procs: &mut Procs<'a>,
+        layout_cache: &mut LayoutCache<'a>,
     ) -> Self {
-        let mut layout_cache = LayoutCache::default();
-
-        from_can(env, can_expr, procs, &mut layout_cache)
+        from_can(env, can_expr, procs, layout_cache)
     }
+
     pub fn to_doc<'b, D, A>(&'b self, alloc: &'b D) -> DocBuilder<'b, D, A>
     where
         D: DocAllocator<'b, A>,
diff --git a/compiler/reporting/tests/test_reporting.rs b/compiler/reporting/tests/test_reporting.rs
index 986494edc6..00ad553745 100644
--- a/compiler/reporting/tests/test_reporting.rs
+++ b/compiler/reporting/tests/test_reporting.rs
@@ -10,21 +10,21 @@ mod helpers;
 #[cfg(test)]
 mod test_reporting {
     use crate::helpers::test_home;
+    use crate::helpers::{can_expr, infer_expr, CanExprOut, ParseErrOut};
     use bumpalo::Bump;
     use roc_module::symbol::{Interns, ModuleId};
     use roc_mono::ir::{Procs, Stmt};
+    use roc_mono::layout::LayoutCache;
     use roc_reporting::report::{
         can_problem, mono_problem, parse_problem, type_problem, Report, BLUE_CODE, BOLD_CODE,
         CYAN_CODE, DEFAULT_PALETTE, GREEN_CODE, MAGENTA_CODE, RED_CODE, RESET_CODE, UNDERLINE_CODE,
         WHITE_CODE, YELLOW_CODE,
     };
+    use roc_reporting::report::{RocDocAllocator, RocDocBuilder};
+    use roc_solve::solve;
     use roc_types::pretty_print::name_all_type_vars;
     use roc_types::subs::Subs;
     use std::path::PathBuf;
-    // use roc_region::all;
-    use crate::helpers::{can_expr, infer_expr, CanExprOut, ParseErrOut};
-    use roc_reporting::report::{RocDocAllocator, RocDocBuilder};
-    use roc_solve::solve;
 
     fn filename_from_string(str: &str) -> PathBuf {
         let mut filename = PathBuf::new();
@@ -87,6 +87,7 @@ mod test_reporting {
             let mut ident_ids = interns.all_ident_ids.remove(&home).unwrap();
 
             // Populate Procs and Subs, and get the low-level Expr from the canonical Expr
+            let mut layout_cache = LayoutCache::default();
             let mut mono_env = roc_mono::ir::Env {
                 arena: &arena,
                 subs: &mut subs,
@@ -94,7 +95,8 @@ mod test_reporting {
                 home,
                 ident_ids: &mut ident_ids,
             };
-            let _mono_expr = Stmt::new(&mut mono_env, loc_expr.value, &mut procs);
+            let _mono_expr =
+                Stmt::new(&mut mono_env, loc_expr.value, &mut procs, &mut layout_cache);
         }
 
         Ok((unify_problems, can_problems, mono_problems, home, interns))