diff --git a/compiler/forget/src/HIR/HIR.ts b/compiler/forget/src/HIR/HIR.ts
index 89538ca2a3..59a3988932 100644
--- a/compiler/forget/src/HIR/HIR.ts
+++ b/compiler/forget/src/HIR/HIR.ts
@@ -538,6 +538,13 @@ export type MethodCall = {
   loc: SourceLocation;
 };
 
+export type CallExpression = {
+  kind: "CallExpression";
+  callee: Place;
+  args: Array<Place | SpreadPattern>;
+  loc: SourceLocation;
+};
+
 /**
  * The value of a given instruction. Note that values are not recursive: complex
  * values such as objects or arrays are always defined by instructions to define
@@ -605,12 +612,7 @@ export type InstructionValue =
       args: Array<Place | SpreadPattern>;
       loc: SourceLocation;
     }
-  | {
-      kind: "CallExpression";
-      callee: Place;
-      args: Array<Place | SpreadPattern>;
-      loc: SourceLocation;
-    }
+  | CallExpression
   | MethodCall
   | {
       kind: "UnaryExpression";
diff --git a/compiler/forget/src/Inference/InferReferenceEffects.ts b/compiler/forget/src/Inference/InferReferenceEffects.ts
index 0a9fbf7ae2..9ed2eca8c2 100644
--- a/compiler/forget/src/Inference/InferReferenceEffects.ts
+++ b/compiler/forget/src/Inference/InferReferenceEffects.ts
@@ -11,6 +11,7 @@ import { Environment } from "../HIR";
 import {
   BasicBlock,
   BlockId,
+  CallExpression,
   Effect,
   HIRFunction,
   IdentifierId,
@@ -707,8 +708,6 @@ function inferBlock(
         continue;
       }
       case "CallExpression": {
-        valueKind = ValueKind.Mutable;
-        effectKind = Effect.Mutate;
         const hook =
           instrValue.callee.identifier.type.kind === "Hook"
             ? instrValue.callee.identifier.type.definition
@@ -716,8 +715,42 @@ function inferBlock(
         if (hook !== null) {
           effectKind = hook.effectKind;
           valueKind = hook.valueKind;
+          break;
         }
-        break;
+
+        const signature = getFunctionCallSignature(
+          env,
+          instrValue.callee.identifier.type
+        );
+
+        const effects =
+          signature !== null
+            ? getMethodCallEffects(instrValue, signature)
+            : null;
+        for (let i = 0; i < instrValue.args.length; i++) {
+          const arg = instrValue.args[i];
+          const place = arg.kind === "Identifier" ? arg : arg.place;
+          if (effects !== null) {
+            // If effects are inferred for an argument, we should fail invalid
+            // mutating effects
+            state.referenceAndCheckError(place, effects[i]);
+          } else {
+            state.reference(place, Effect.Mutate);
+          }
+        }
+        if (signature !== null) {
+          state.referenceAndCheckError(
+            instrValue.callee,
+            signature.calleeEffect
+          );
+        } else {
+          state.reference(instrValue.callee, Effect.Mutate);
+        }
+
+        state.initialize(instrValue, ValueKind.Mutable);
+        state.define(instr.lvalue, instrValue);
+        instr.lvalue.effect = Effect.Mutate;
+        continue;
       }
       case "MethodCall": {
         invariant(
@@ -1003,7 +1036,7 @@ function getFunctionCallSignature(
  * @returns Inferred effects of function arguments, or null if inference fails.
  */
 function getMethodCallEffects(
-  fn: MethodCall,
+  fn: MethodCall | CallExpression,
   sig: FunctionSignature
 ): Array<Effect> | null {
   const results = [];
diff --git a/compiler/forget/src/__tests__/fixtures/compiler/globals-Boolean.expect.md b/compiler/forget/src/__tests__/fixtures/compiler/globals-Boolean.expect.md
index 642b273630..84b9eb6b94 100644
--- a/compiler/forget/src/__tests__/fixtures/compiler/globals-Boolean.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/compiler/globals-Boolean.expect.md
@@ -17,25 +17,29 @@ import { unstable_useMemoCache as useMemoCache } from "react";
 function Component(props) {
   const $ = useMemoCache(3);
   let t0;
-  let x;
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
-    x = {};
-    t0 = Boolean(x);
+    t0 = {};
     $[0] = t0;
-    $[1] = x;
   } else {
     t0 = $[0];
-    x = $[1];
   }
-  const y = t0;
+  const x = t0;
   let t1;
-  if ($[2] === Symbol.for("react.memo_cache_sentinel")) {
-    t1 = [x, y];
-    $[2] = t1;
+  if ($[1] === Symbol.for("react.memo_cache_sentinel")) {
+    t1 = Boolean(x);
+    $[1] = t1;
   } else {
-    t1 = $[2];
+    t1 = $[1];
   }
-  return t1;
+  const y = t1;
+  let t2;
+  if ($[2] === Symbol.for("react.memo_cache_sentinel")) {
+    t2 = [x, y];
+    $[2] = t2;
+  } else {
+    t2 = $[2];
+  }
+  return t2;
 }
 
 ```
diff --git a/compiler/forget/src/__tests__/fixtures/compiler/globals-Number.expect.md b/compiler/forget/src/__tests__/fixtures/compiler/globals-Number.expect.md
index a8ce51aae2..7a29e07de6 100644
--- a/compiler/forget/src/__tests__/fixtures/compiler/globals-Number.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/compiler/globals-Number.expect.md
@@ -17,25 +17,29 @@ import { unstable_useMemoCache as useMemoCache } from "react";
 function Component(props) {
   const $ = useMemoCache(3);
   let t0;
-  let x;
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
-    x = {};
-    t0 = Number(x);
+    t0 = {};
     $[0] = t0;
-    $[1] = x;
   } else {
     t0 = $[0];
-    x = $[1];
   }
-  const y = t0;
+  const x = t0;
   let t1;
-  if ($[2] === Symbol.for("react.memo_cache_sentinel")) {
-    t1 = [x, y];
-    $[2] = t1;
+  if ($[1] === Symbol.for("react.memo_cache_sentinel")) {
+    t1 = Number(x);
+    $[1] = t1;
   } else {
-    t1 = $[2];
+    t1 = $[1];
   }
-  return t1;
+  const y = t1;
+  let t2;
+  if ($[2] === Symbol.for("react.memo_cache_sentinel")) {
+    t2 = [x, y];
+    $[2] = t2;
+  } else {
+    t2 = $[2];
+  }
+  return t2;
 }
 
 ```
diff --git a/compiler/forget/src/__tests__/fixtures/compiler/globals-String.expect.md b/compiler/forget/src/__tests__/fixtures/compiler/globals-String.expect.md
index 8955b4b326..1efd363393 100644
--- a/compiler/forget/src/__tests__/fixtures/compiler/globals-String.expect.md
+++ b/compiler/forget/src/__tests__/fixtures/compiler/globals-String.expect.md
@@ -17,25 +17,29 @@ import { unstable_useMemoCache as useMemoCache } from "react";
 function Component(props) {
   const $ = useMemoCache(3);
   let t0;
-  let x;
   if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
-    x = {};
-    t0 = String(x);
+    t0 = {};
     $[0] = t0;
-    $[1] = x;
   } else {
     t0 = $[0];
-    x = $[1];
   }
-  const y = t0;
+  const x = t0;
   let t1;
-  if ($[2] === Symbol.for("react.memo_cache_sentinel")) {
-    t1 = [x, y];
-    $[2] = t1;
+  if ($[1] === Symbol.for("react.memo_cache_sentinel")) {
+    t1 = String(x);
+    $[1] = t1;
   } else {
-    t1 = $[2];
+    t1 = $[1];
   }
-  return t1;
+  const y = t1;
+  let t2;
+  if ($[2] === Symbol.for("react.memo_cache_sentinel")) {
+    t2 = [x, y];
+    $[2] = t2;
+  } else {
+    t2 = $[2];
+  }
+  return t2;
 }
 
 ```