diff --git a/src/cargo/core/compiler/context/mod.rs b/src/cargo/core/compiler/context/mod.rs
index 153c65f78..3d8967ee9 100644
--- a/src/cargo/core/compiler/context/mod.rs
+++ b/src/cargo/core/compiler/context/mod.rs
@@ -206,19 +206,21 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
 
             // If the unit has a build script, add `OUT_DIR` to the
             // environment variables.
-            for dep in &self.bcx.unit_graph[unit] {
-                if dep.unit.mode.is_run_custom_build() {
-                    let out_dir = self
-                        .files()
-                        .build_script_out_dir(&dep.unit)
-                        .display()
-                        .to_string();
-                    let script_meta = self.get_run_build_script_metadata(&dep.unit);
-                    self.compilation
-                        .extra_env
-                        .entry(script_meta)
-                        .or_insert_with(Vec::new)
-                        .push(("OUT_DIR".to_string(), out_dir));
+            if unit.target.is_lib() {
+                for dep in &self.bcx.unit_graph[unit] {
+                    if dep.unit.mode.is_run_custom_build() {
+                        let out_dir = self
+                            .files()
+                            .build_script_out_dir(&dep.unit)
+                            .display()
+                            .to_string();
+                        let script_meta = self.get_run_build_script_metadata(&dep.unit);
+                        self.compilation
+                            .extra_env
+                            .entry(script_meta)
+                            .or_insert_with(Vec::new)
+                            .push(("OUT_DIR".to_string(), out_dir));
+                    }
                 }
             }
 
diff --git a/src/cargo/core/compiler/mod.rs b/src/cargo/core/compiler/mod.rs
index 4b6565b81..ea05e0733 100644
--- a/src/cargo/core/compiler/mod.rs
+++ b/src/cargo/core/compiler/mod.rs
@@ -12,7 +12,7 @@ mod job;
 mod job_queue;
 mod layout;
 mod links;
-pub mod lto;
+mod lto;
 mod output_depinfo;
 pub mod rustdoc;
 pub mod standard_lib;
diff --git a/src/cargo/ops/cargo_compile.rs b/src/cargo/ops/cargo_compile.rs
index 41117d701..e10b19952 100644
--- a/src/cargo/ops/cargo_compile.rs
+++ b/src/cargo/ops/cargo_compile.rs
@@ -25,13 +25,10 @@
 use std::collections::{BTreeSet, HashMap, HashSet};
 use std::ffi::OsString;
 use std::hash::{Hash, Hasher};
-use std::iter;
 use std::sync::Arc;
 
-use crate::core::compiler::lto;
 use crate::core::compiler::unit_dependencies::build_unit_dependencies;
 use crate::core::compiler::unit_graph::{self, UnitDep, UnitGraph};
-use crate::core::compiler::Layout;
 use crate::core::compiler::{standard_lib, TargetInfo};
 use crate::core::compiler::{BuildConfig, BuildContext, Compilation, Context};
 use crate::core::compiler::{CompileKind, CompileMode, CompileTarget, RustcTargetData, Unit};