diff --git a/components/fallible/Cargo.toml b/components/fallible/Cargo.toml
index 7b5291304be1..e8f5314693b9 100644
--- a/components/fallible/Cargo.toml
+++ b/components/fallible/Cargo.toml
@@ -10,7 +10,7 @@ name = "fallible"
 path = "lib.rs"
 
 [dependencies]
-smallvec = { version = "0.6", features = ["std", "union"] }
+smallvec = "0.6"
 hashglobe = { path = "../hashglobe" }
 
 # This crate effectively does nothing except if the `known_system_malloc`
diff --git a/components/malloc_size_of/Cargo.toml b/components/malloc_size_of/Cargo.toml
index 7ecb2d594227..cd05b5d50c09 100644
--- a/components/malloc_size_of/Cargo.toml
+++ b/components/malloc_size_of/Cargo.toml
@@ -37,7 +37,7 @@ serde_bytes = { version = "0.10", optional = true }
 servo_arc = { path = "../servo_arc" }
 servo_channel = { path = "../channel", optional = true }
 smallbitvec = "2.1.0"
-smallvec = { version = "0.6", features = ["std", "union"] }
+smallvec = "0.6"
 string_cache = { version = "0.7", optional = true }
 thin-slice = "0.1.0"
 time = { version = "0.1.17", optional = true }
diff --git a/components/selectors/Cargo.toml b/components/selectors/Cargo.toml
index 76cb50bcf82e..f7a0a6a85ce0 100644
--- a/components/selectors/Cargo.toml
+++ b/components/selectors/Cargo.toml
@@ -28,7 +28,7 @@ fxhash = "0.2"
 phf = "0.7.18"
 precomputed-hash = "0.1"
 servo_arc = { version = "0.1", path = "../servo_arc" }
-smallvec = { version = "0.6", features = ["std", "union"] }
+smallvec = "0.6"
 thin-slice = "0.1.0"
 
 [build-dependencies]
diff --git a/components/style/Cargo.toml b/components/style/Cargo.toml
index 3c975d7520c0..1b41545dcae1 100644
--- a/components/style/Cargo.toml
+++ b/components/style/Cargo.toml
@@ -62,7 +62,7 @@ servo_atoms = {path = "../atoms", optional = true}
 servo_channel = {path = "../channel", optional = true}
 servo_config = {path = "../config", optional = true}
 smallbitvec = "2.1.1"
-smallvec = { version = "0.6", features = ["std", "union"] }
+smallvec = "0.6"
 string_cache = { version = "0.7", optional = true }
 style_derive = {path = "../style_derive"}
 style_traits = {path = "../style_traits"}