diff --git a/cranelift/codegen/Cargo.toml b/cranelift/codegen/Cargo.toml
index c5f58f9086..dfb1277670 100644
--- a/cranelift/codegen/Cargo.toml
+++ b/cranelift/codegen/Cargo.toml
@@ -24,7 +24,7 @@ log = { version = "0.4.6", default-features = false }
 serde = { version = "1.0.94", features = ["derive"], optional = true }
 bincode = { version = "1.2.1", optional = true }
 gimli = { version = "0.26.0", default-features = false, features = ["write"], optional = true }
-smallvec = { version = "1.6.1" }
+smallvec = { version = "1.6.1", features = ["union"] }
 regalloc2 = { version = "0.4.1", features = ["checker"] }
 souper-ir = { version = "2.1.0", optional = true }
 sha2 = { version = "0.9.0", optional = true }
diff --git a/cranelift/egraph/Cargo.toml b/cranelift/egraph/Cargo.toml
index 819ad25159..51683c4ae8 100644
--- a/cranelift/egraph/Cargo.toml
+++ b/cranelift/egraph/Cargo.toml
@@ -11,7 +11,7 @@ edition = "2021"
 [dependencies]
 cranelift-entity = { path = "../entity", version = "0.89.0" }
 log = { version = "0.4.6", default-features = false }
-smallvec = { version = "1.6.1" }
+smallvec = { version = "1.6.1", features = ["union"] }
 indexmap = { version = "1.9.1" }
 hashbrown = { version = "0.12.2", features = ["raw"] }
 fxhash = "0.2.1"
diff --git a/cranelift/frontend/Cargo.toml b/cranelift/frontend/Cargo.toml
index 80460f9590..fe0624a6a5 100644
--- a/cranelift/frontend/Cargo.toml
+++ b/cranelift/frontend/Cargo.toml
@@ -15,7 +15,7 @@ cranelift-codegen = { path = "../codegen", version = "0.89.0", default-features
 target-lexicon = "0.12"
 log = { version = "0.4.6", default-features = false }
 hashbrown = { version = "0.12", optional = true }
-smallvec = { version = "1.6.1" }
+smallvec = { version = "1.6.1", features = ["union"] }
 
 [features]
 default = ["std"]
diff --git a/cranelift/interpreter/Cargo.toml b/cranelift/interpreter/Cargo.toml
index cbabad0ef5..7410e35a3a 100644
--- a/cranelift/interpreter/Cargo.toml
+++ b/cranelift/interpreter/Cargo.toml
@@ -14,7 +14,7 @@ edition = "2021"
 cranelift-codegen = { path = "../codegen", version = "0.89.0" }
 cranelift-entity = { path = "../entity", version = "0.89.0" }
 log = { version = "0.4.8", default-features = false }
-smallvec = "1.6.1"
+smallvec = { version = "1.6.1", features = ["union"] }
 thiserror = "1.0.15"
 
 [target.x86_64-pc-windows-gnu.dependencies]
diff --git a/cranelift/reader/Cargo.toml b/cranelift/reader/Cargo.toml
index 6743033141..1125692ce9 100644
--- a/cranelift/reader/Cargo.toml
+++ b/cranelift/reader/Cargo.toml
@@ -11,7 +11,7 @@ edition = "2021"
 
 [dependencies]
 cranelift-codegen = { path = "../codegen", version = "0.89.0" }
-smallvec = "1.6.1"
+smallvec = { version = "1.6.1", features = ["union"] }
 target-lexicon = "0.12"
 
 [badges]
diff --git a/cranelift/wasm/Cargo.toml b/cranelift/wasm/Cargo.toml
index 5e4c0c2b02..0460f2f4a1 100644
--- a/cranelift/wasm/Cargo.toml
+++ b/cranelift/wasm/Cargo.toml
@@ -21,7 +21,7 @@ hashbrown = { version = "0.12", optional = true }
 itertools = "0.10.0"
 log = { version = "0.4.6", default-features = false }
 serde = { version = "1.0.94", features = ["derive"], optional = true }
-smallvec = "1.6.1"
+smallvec = { version = "1.6.1", features = ["union"] }
 
 [dev-dependencies]
 wat = "1.0.47"
diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
index 1111473d47..9dc45c9da4 100644
--- a/fuzz/Cargo.toml
+++ b/fuzz/Cargo.toml
@@ -18,7 +18,7 @@ cranelift-interpreter = { path = "../cranelift/interpreter" }
 cranelift-fuzzgen = { path = "../cranelift/fuzzgen" }
 libfuzzer-sys = { version = "0.4.0", features = ["arbitrary-derive"] }
 target-lexicon = "0.12"
-smallvec = "1.6.1"
+smallvec = { version = "1.6.1", features = ["union"] }
 wasmtime = { path = "../crates/wasmtime" }
 wasmtime-fuzzing = { path = "../crates/fuzzing" }
 component-test-util = { path = "../crates/misc/component-test-util" }