diff --git a/src/cargo/ops/cargo_compile.rs b/src/cargo/ops/cargo_compile.rs
index 1f8df9626aa..0a1d83c3086 100644
--- a/src/cargo/ops/cargo_compile.rs
+++ b/src/cargo/ops/cargo_compile.rs
@@ -22,7 +22,8 @@
 //!       previously compiled dependency
 //!
 
-use std::collections::{HashMap, HashSet};
+use std::collections::{BTreeSet, HashMap, HashSet};
+use std::iter::FromIterator;
 use std::path::PathBuf;
 use std::sync::Arc;
 
@@ -110,22 +111,33 @@ impl Packages {
     }
 
     pub fn to_package_id_specs(&self, ws: &Workspace<'_>) -> CargoResult<Vec<PackageIdSpec>> {
-        let specs = match *self {
+        let specs = match self {
             Packages::All => ws
                 .members()
                 .map(Package::package_id)
                 .map(PackageIdSpec::from_package_id)
                 .collect(),
-            Packages::OptOut(ref opt_out) => ws
-                .members()
-                .map(Package::package_id)
-                .map(PackageIdSpec::from_package_id)
-                .filter(|p| opt_out.iter().position(|x| *x == p.name()).is_none())
-                .collect(),
-            Packages::Packages(ref packages) if packages.is_empty() => {
+            Packages::OptOut(opt_out) => {
+                let mut opt_out = BTreeSet::from_iter(opt_out.iter().cloned());
+                let packages = ws
+                    .members()
+                    .filter(|pkg| !opt_out.remove(pkg.name().as_str()))
+                    .map(Package::package_id)
+                    .map(PackageIdSpec::from_package_id)
+                    .collect();
+                if !opt_out.is_empty() {
+                    ws.config().shell().warn(format!(
+                        "excluded package(s) {} not found in workspace `{}`",
+                        opt_out.iter().map(|x| x.as_ref()).collect::<Vec<_>>().join(", "),
+                        ws.root().display(),
+                    ))?;
+                }
+                packages
+            },
+            Packages::Packages(packages) if packages.is_empty() => {
                 vec![PackageIdSpec::from_package_id(ws.current()?.package_id())]
             }
-            Packages::Packages(ref packages) => packages
+            Packages::Packages(packages) => packages
                 .iter()
                 .map(|p| PackageIdSpec::parse(p))
                 .collect::<CargoResult<Vec<_>>>()?,
@@ -152,11 +164,11 @@ impl Packages {
         let packages: Vec<_> = match self {
             Packages::Default => ws.default_members().collect(),
             Packages::All => ws.members().collect(),
-            Packages::OptOut(ref opt_out) => ws
+            Packages::OptOut(opt_out) => ws
                 .members()
                 .filter(|pkg| !opt_out.iter().any(|name| pkg.name().as_str() == name))
                 .collect(),
-            Packages::Packages(ref pkgs) => pkgs
+            Packages::Packages(packages) => packages
                 .iter()
                 .map(|name| {
                     ws.members()
diff --git a/tests/testsuite/check.rs b/tests/testsuite/check.rs
index 390293d0f8e..06cd2c2fc27 100644
--- a/tests/testsuite/check.rs
+++ b/tests/testsuite/check.rs
@@ -427,6 +427,20 @@ fn check_virtual_all_implied() {
         .run();
 }
 
+#[test]
+fn exclude_warns_on_non_existing_package() {
+    let p = project().file("src/lib.rs", "").build();
+    p.cargo("check --all --exclude bar")
+        .with_stdout("")
+        .with_stderr(
+            r#"[WARNING] excluded package(s) bar not found in workspace `[CWD]`
+[CHECKING] foo v0.0.1 ([CWD])
+[FINISHED] dev [unoptimized + debuginfo] target(s) in [..]
+"#,
+        )
+        .run();
+}
+
 #[test]
 fn targets_selected_default() {
     let foo = project()