diff --git a/crates/component-macro/src/component.rs b/crates/component-macro/src/component.rs
index 3a408dd83fbb..a9f693bd5462 100644
--- a/crates/component-macro/src/component.rs
+++ b/crates/component-macro/src/component.rs
@@ -359,6 +359,7 @@ fn expand_record_for_component_type(
     let mut lower_field_declarations = TokenStream::new();
     let mut abi_list = TokenStream::new();
     let mut unique_types = HashSet::new();
+    let mut may_require_realloc = TokenStream::new();
 
     for (index, syn::Field { ident, ty, .. }) in fields.iter().enumerate() {
         let generic = format_ident!("T{}", index);
@@ -371,6 +372,9 @@ fn expand_record_for_component_type(
         abi_list.extend(quote!(
             <#ty as #wt::component::ComponentType>::ABI,
         ));
+        may_require_realloc.extend(quote!(
+            <#ty as #wt::component::ComponentType>::MAY_REQUIRE_REALLOC ||
+        ));
 
         unique_types.insert(ty);
     }
@@ -408,6 +412,7 @@ fn expand_record_for_component_type(
 
             const ABI: #internal::CanonicalAbiInfo =
                 #internal::CanonicalAbiInfo::record_static(&[#abi_list]);
+            const MAY_REQUIRE_REALLOC: bool = #may_require_realloc false;
 
             #[inline]
             fn typecheck(
@@ -961,6 +966,7 @@ impl Expander for ComponentTypeExpander {
         let mut lower_generic_args = TokenStream::new();
         let mut abi_list = TokenStream::new();
         let mut unique_types = HashSet::new();
+        let mut may_require_realloc = TokenStream::new();
 
         for (index, VariantCase { attrs, ident, ty }) in cases.iter().enumerate() {
             let rename = find_rename(attrs)?;
@@ -969,6 +975,9 @@ impl Expander for ComponentTypeExpander {
 
             if let Some(ty) = ty {
                 abi_list.extend(quote!(Some(<#ty as #wt::component::ComponentType>::ABI),));
+                may_require_realloc.extend(quote!(
+                    <#ty as #wt::component::ComponentType>::MAY_REQUIRE_REALLOC ||
+                ));
 
                 case_names_and_checks.extend(
                     quote!((#name, Some(<#ty as #wt::component::ComponentType>::typecheck)),),
@@ -1032,6 +1041,7 @@ impl Expander for ComponentTypeExpander {
 
                 const ABI: #internal::CanonicalAbiInfo =
                     #internal::CanonicalAbiInfo::variant_static(&[#abi_list]);
+                const MAY_REQUIRE_REALLOC: bool = #may_require_realloc false;
             }
 
             unsafe impl #impl_generics #internal::ComponentVariant for #name #ty_generics #where_clause {
@@ -1093,6 +1103,7 @@ impl Expander for ComponentTypeExpander {
 
                 const ABI: #internal::CanonicalAbiInfo =
                     #internal::CanonicalAbiInfo::enum_(#cases_len);
+                const MAY_REQUIRE_REALLOC: bool = false;
             }
 
             unsafe impl #internal::ComponentVariant for #name {
diff --git a/crates/wasmtime/src/runtime/component/func/typed.rs b/crates/wasmtime/src/runtime/component/func/typed.rs
index 26502343504e..c986ca815ce6 100644
--- a/crates/wasmtime/src/runtime/component/func/typed.rs
+++ b/crates/wasmtime/src/runtime/component/func/typed.rs
@@ -959,6 +959,7 @@ macro_rules! forward_type_impls {
             type Lower = <$b as ComponentType>::Lower;
 
             const ABI: CanonicalAbiInfo = <$b as ComponentType>::ABI;
+            const MAY_REQUIRE_REALLOC: bool = <$b as ComponentType>::MAY_REQUIRE_REALLOC;
 
             #[inline]
             fn typecheck(ty: &InterfaceType, types: &InstanceType<'_>) -> Result<()> {
@@ -1193,6 +1194,7 @@ macro_rules! floats {
             type Lower = ValRaw;
 
             const ABI: CanonicalAbiInfo = CanonicalAbiInfo::$abi;
+            const MAY_REQUIRE_REALLOC: bool = false;
 
             fn typecheck(ty: &InterfaceType, _types: &InstanceType<'_>) -> Result<()> {
                 match ty {
@@ -1310,6 +1312,7 @@ unsafe impl ComponentType for bool {
     type Lower = ValRaw;
 
     const ABI: CanonicalAbiInfo = CanonicalAbiInfo::SCALAR1;
+    const MAY_REQUIRE_REALLOC: bool = false;
 
     fn typecheck(ty: &InterfaceType, _types: &InstanceType<'_>) -> Result<()> {
         match ty {
@@ -1376,6 +1379,7 @@ unsafe impl ComponentType for char {
     type Lower = ValRaw;
 
     const ABI: CanonicalAbiInfo = CanonicalAbiInfo::SCALAR4;
+    const MAY_REQUIRE_REALLOC: bool = false;
 
     fn typecheck(ty: &InterfaceType, _types: &InstanceType<'_>) -> Result<()> {
         match ty {
@@ -2534,6 +2538,7 @@ where
     type Lower = TupleLower<<u32 as ComponentType>::Lower, T::Lower>;
 
     const ABI: CanonicalAbiInfo = CanonicalAbiInfo::variant_static(&[None, Some(T::ABI)]);
+    const MAY_REQUIRE_REALLOC: bool = T::MAY_REQUIRE_REALLOC;
 
     fn typecheck(ty: &InterfaceType, types: &InstanceType<'_>) -> Result<()> {
         match ty {
@@ -2675,6 +2680,7 @@ where
     type Lower = ResultLower<T::Lower, E::Lower>;
 
     const ABI: CanonicalAbiInfo = CanonicalAbiInfo::variant_static(&[Some(T::ABI), Some(E::ABI)]);
+    const MAY_REQUIRE_REALLOC: bool = T::MAY_REQUIRE_REALLOC || E::MAY_REQUIRE_REALLOC;
 
     fn typecheck(ty: &InterfaceType, types: &InstanceType<'_>) -> Result<()> {
         match ty {
@@ -3032,6 +3038,7 @@ macro_rules! impl_component_ty_for_tuples {
             const ABI: CanonicalAbiInfo = CanonicalAbiInfo::record_static(&[
                 $($t::ABI),*
             ]);
+            const MAY_REQUIRE_REALLOC: bool = false $(|| $t::MAY_REQUIRE_REALLOC)*;
 
             const IS_RUST_UNIT_TYPE: bool = {
                 let mut _is_unit = true;
diff --git a/crates/wasmtime/src/runtime/component/resources/any.rs b/crates/wasmtime/src/runtime/component/resources/any.rs
index 4d5d7c800590..17c933f134d1 100644
--- a/crates/wasmtime/src/runtime/component/resources/any.rs
+++ b/crates/wasmtime/src/runtime/component/resources/any.rs
@@ -272,6 +272,7 @@ impl ResourceAny {
 
 unsafe impl ComponentType for ResourceAny {
     const ABI: CanonicalAbiInfo = CanonicalAbiInfo::SCALAR4;
+    const MAY_REQUIRE_REALLOC: bool = false;
 
     type Lower = <u32 as ComponentType>::Lower;
 
diff --git a/crates/wasmtime/src/runtime/component/resources/host.rs b/crates/wasmtime/src/runtime/component/resources/host.rs
index ed0d067b17b8..e1d363c696b4 100644
--- a/crates/wasmtime/src/runtime/component/resources/host.rs
+++ b/crates/wasmtime/src/runtime/component/resources/host.rs
@@ -312,6 +312,7 @@ where
     D: PartialEq + Send + Sync + Copy + 'static,
 {
     const ABI: CanonicalAbiInfo = CanonicalAbiInfo::SCALAR4;
+    const MAY_REQUIRE_REALLOC: bool = false;
 
     type Lower = <u32 as ComponentType>::Lower;
 
diff --git a/crates/wasmtime/src/runtime/component/resources/host_dynamic.rs b/crates/wasmtime/src/runtime/component/resources/host_dynamic.rs
index c3491b3ba2ae..72b9d4c69ea8 100644
--- a/crates/wasmtime/src/runtime/component/resources/host_dynamic.rs
+++ b/crates/wasmtime/src/runtime/component/resources/host_dynamic.rs
@@ -144,6 +144,7 @@ impl ResourceDynamic {
 }
 
 unsafe impl ComponentType for ResourceDynamic {
+    const MAY_REQUIRE_REALLOC: bool = false;
     const ABI: CanonicalAbiInfo = HostResource::<Dynamic, u32>::ABI;
     type Lower = crate::ValRaw;
 
diff --git a/crates/wasmtime/src/runtime/component/resources/host_static.rs b/crates/wasmtime/src/runtime/component/resources/host_static.rs
index 2d45813c0f6e..a85cfefa0ff7 100644
--- a/crates/wasmtime/src/runtime/component/resources/host_static.rs
+++ b/crates/wasmtime/src/runtime/component/resources/host_static.rs
@@ -217,6 +217,7 @@ where
 
 unsafe impl<T: 'static> ComponentType for Resource<T> {
     const ABI: CanonicalAbiInfo = HostResource::<Static<T>, ()>::ABI;
+    const MAY_REQUIRE_REALLOC: bool = false;
     type Lower = crate::ValRaw;
 
     fn typecheck(ty: &InterfaceType, types: &InstanceType<'_>) -> Result<()> {