diff --git a/Cargo.toml b/Cargo.toml
index 829a3889e01..7f329f2226b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -78,7 +78,6 @@ bytecount = "0.6"
 dunce = "1.0"
 ignore = "0.4.11"
 itertools = "0.8"
-lazy_static = "1.0.0"
 log = "0.4"
 regex = "1.0"
 thiserror = "1.0"
@@ -104,6 +103,7 @@ toml = { version = "0.5", optional = true }
 
 [dev-dependencies]
 env_logger = "0.7"
+lazy_static = "1.0.0"
 
 [dependencies.rustc_ast]
 package = "rustc-ap-rustc_ast"
diff --git a/src/formatting/modules.rs b/src/formatting/modules.rs
index bbd502d49b6..2570d9b1a65 100644
--- a/src/formatting/modules.rs
+++ b/src/formatting/modules.rs
@@ -21,10 +21,6 @@ mod visitor;
 
 type FileModMap<'ast> = BTreeMap<FileName, Module<'ast>>;
 
-lazy_static! {
-    static ref CFG_IF: Symbol = Symbol::intern("cfg_if");
-}
-
 /// Represents module with its inner attributes.
 #[derive(Debug, Clone)]
 pub(crate) struct Module<'a> {
@@ -479,8 +475,8 @@ fn find_path_value(attrs: &[ast::Attribute]) -> Option<Symbol> {
 fn is_cfg_if(item: &ast::Item) -> bool {
     match item.kind {
         ast::ItemKind::MacCall(ref mac) => {
-            if let Some(first_segment) = mac.path.segments.first() {
-                if first_segment.ident.name == *CFG_IF {
+            if let Some(last_segment) = mac.path.segments.last() {
+                if last_segment.ident.name.as_str() == "cfg_if" {
                     return true;
                 }
             }
diff --git a/src/formatting/modules/visitor.rs b/src/formatting/modules/visitor.rs
index f221c3ea35d..37100a37a26 100644
--- a/src/formatting/modules/visitor.rs
+++ b/src/formatting/modules/visitor.rs
@@ -49,9 +49,9 @@ impl<'a, 'ast: 'a> CfgIfVisitor<'a> {
         // extern crate cfg_if;
         // cfg_if! {..}
         // ```
-        match mac.path.segments.first() {
-            Some(first_segment) => {
-                if first_segment.ident.name != Symbol::intern("cfg_if") {
+        match mac.path.segments.last() {
+            Some(last_segment) => {
+                if last_segment.ident.name != Symbol::intern("cfg_if") {
                     return Err("Expected cfg_if");
                 }
             }
diff --git a/src/lib.rs b/src/lib.rs
index a0005ea151d..d19f8144da2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,11 +2,13 @@
 #![warn(unreachable_pub)]
 #![feature(cell_leak)]
 
-#[macro_use]
-extern crate lazy_static;
 #[macro_use]
 extern crate log;
 
+#[cfg(test)]
+#[macro_use]
+extern crate lazy_static;
+
 use std::path::PathBuf;
 
 pub use crate::config::{