diff --git a/tests/ui/feature-gates/feature-gate-link_cfg.rs b/tests/ui/feature-gates/feature-gate-link_cfg.rs
index d30ee3bcfdb1..286c3d0a4977 100644
--- a/tests/ui/feature-gates/feature-gate-link_cfg.rs
+++ b/tests/ui/feature-gates/feature-gate-link_cfg.rs
@@ -1,4 +1,4 @@
-#[link(name = "foo", cfg(foo))]
+#[link(name = "foo", cfg(false))]
 //~^ ERROR: is unstable
 extern "C" {}
 
diff --git a/tests/ui/feature-gates/feature-gate-link_cfg.stderr b/tests/ui/feature-gates/feature-gate-link_cfg.stderr
index bfe7f74a9213..0e9707c6c962 100644
--- a/tests/ui/feature-gates/feature-gate-link_cfg.stderr
+++ b/tests/ui/feature-gates/feature-gate-link_cfg.stderr
@@ -1,8 +1,8 @@
 error[E0658]: link cfg is unstable
   --> $DIR/feature-gate-link_cfg.rs:1:22
    |
-LL | #[link(name = "foo", cfg(foo))]
-   |                      ^^^^^^^^
+LL | #[link(name = "foo", cfg(false))]
+   |                      ^^^^^^^^^^
    |
    = help: add `#![feature(link_cfg)]` to the crate attributes to enable
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
diff --git a/tests/ui/link-native-libs/link-cfg-works.rs b/tests/ui/link-native-libs/link-cfg-works.rs
index 7b936bc43b1a..0e02933ce01c 100644
--- a/tests/ui/link-native-libs/link-cfg-works.rs
+++ b/tests/ui/link-native-libs/link-cfg-works.rs
@@ -7,7 +7,7 @@
 extern crate link_cfg_works_transitive_dylib;
 extern crate link_cfg_works_transitive_rlib;
 
-#[link(name = "foo", cfg(foo))]
+#[link(name = "foo", cfg(false))]
 extern "C" {}
 
 fn main() {}
diff --git a/tests/ui/macros/cfg.rs b/tests/ui/macros/cfg.rs
index d992ec82e2fd..f0c51b2942f1 100644
--- a/tests/ui/macros/cfg.rs
+++ b/tests/ui/macros/cfg.rs
@@ -2,5 +2,6 @@ fn main() {
     cfg!(); //~ ERROR macro requires a cfg-pattern
     cfg!(123); //~ ERROR malformed `cfg` macro input
     cfg!(foo = 123); //~ ERROR malformed `cfg` macro input
-    cfg!(foo, bar); //~ ERROR expected 1 cfg-pattern
+    cfg!(false, false); //~ ERROR expected 1 cfg-pattern
+    cfg!(foo); //~ WARN unexpected `cfg` condition name: `foo`
 }
diff --git a/tests/ui/macros/cfg.stderr b/tests/ui/macros/cfg.stderr
index 9a4c187f37b2..06529a5b7a61 100644
--- a/tests/ui/macros/cfg.stderr
+++ b/tests/ui/macros/cfg.stderr
@@ -29,9 +29,20 @@ LL |     cfg!(foo = 123);
 error: expected 1 cfg-pattern
   --> $DIR/cfg.rs:5:5
    |
-LL |     cfg!(foo, bar);
-   |     ^^^^^^^^^^^^^^
+LL |     cfg!(false, false);
+   |     ^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 4 previous errors
+warning: unexpected `cfg` condition name: `foo`
+  --> $DIR/cfg.rs:6:10
+   |
+LL |     cfg!(foo);
+   |          ^^^
+   |
+   = help: expected names are: `FALSE` and `test` and 31 more
+   = help: to expect this configuration use `--check-cfg=cfg(foo)`
+   = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more information about checking conditional configuration
+   = note: `#[warn(unexpected_cfgs)]` on by default
+
+error: aborting due to 4 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0539`.
diff --git a/tests/ui/macros/cfg_select.rs b/tests/ui/macros/cfg_select.rs
index 2a627cc05b93..a54c385747fa 100644
--- a/tests/ui/macros/cfg_select.rs
+++ b/tests/ui/macros/cfg_select.rs
@@ -89,9 +89,11 @@ cfg_select! {
 cfg_select! {
     a + 1 => {}
     //~^ ERROR expected one of `(`, `::`, `=>`, or `=`, found `+`
+    //~| WARN unexpected `cfg` condition name
 }
 
 cfg_select! {
     cfg!() => {}
     //~^ ERROR expected one of `(`, `::`, `=>`, or `=`, found `!`
+    //~| WARN unexpected `cfg` condition name
 }
diff --git a/tests/ui/macros/cfg_select.stderr b/tests/ui/macros/cfg_select.stderr
index 3a5d2b0a1e1e..d79e1b9b5c10 100644
--- a/tests/ui/macros/cfg_select.stderr
+++ b/tests/ui/macros/cfg_select.stderr
@@ -60,12 +60,32 @@ LL |     a + 1 => {}
    |       ^ expected one of `(`, `::`, `=>`, or `=`
 
 error: expected one of `(`, `::`, `=>`, or `=`, found `!`
-  --> $DIR/cfg_select.rs:95:8
+  --> $DIR/cfg_select.rs:96:8
    |
 LL |     cfg!() => {}
    |        ^ expected one of `(`, `::`, `=>`, or `=`
 
-error: aborting due to 9 previous errors; 1 warning emitted
+warning: unexpected `cfg` condition name: `a`
+  --> $DIR/cfg_select.rs:90:5
+   |
+LL |     a + 1 => {}
+   |     ^ help: found config with similar value: `target_feature = "a"`
+   |
+   = help: expected names are: `FALSE` and `test` and 31 more
+   = help: to expect this configuration use `--check-cfg=cfg(a)`
+   = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more information about checking conditional configuration
+   = note: `#[warn(unexpected_cfgs)]` on by default
+
+warning: unexpected `cfg` condition name: `cfg`
+  --> $DIR/cfg_select.rs:96:5
+   |
+LL |     cfg!() => {}
+   |     ^^^
+   |
+   = help: to expect this configuration use `--check-cfg=cfg(cfg)`
+   = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more information about checking conditional configuration
+
+error: aborting due to 9 previous errors; 3 warnings emitted
 
 Some errors have detailed explanations: E0537, E0539.
 For more information about an error, try `rustc --explain E0537`.