Address review comments

src/test/ui/deduplicate-diagnostics-2.deduplicate.stderr

@@ -0,0 +1,28 @@
+warning: floating-point types cannot be used in patterns
+  --> $DIR/deduplicate-diagnostics-2.rs:7:9
+   |
+LL |         1.0 => {}
+   |         ^^^
+   |
+   = note: `#[warn(illegal_floating_point_literal_pattern)]` on by default
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #41620 <https://github.com/rust-lang/rust/issues/41620>
+
+warning: floating-point types cannot be used in patterns
+  --> $DIR/deduplicate-diagnostics-2.rs:11:9
+   |
+LL |         2.0 => {}
+   |         ^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #41620 <https://github.com/rust-lang/rust/issues/41620>
+
+warning: floating-point types cannot be used in patterns
+  --> $DIR/deduplicate-diagnostics-2.rs:7:9
+   |
+LL |         1.0 => {}
+   |         ^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #41620 <https://github.com/rust-lang/rust/issues/41620>
+

src/test/ui/deduplicate-diagnostics-2.duplicate.stderr

@@ -0,0 +1,37 @@
+warning: floating-point types cannot be used in patterns
+  --> $DIR/deduplicate-diagnostics-2.rs:7:9
+   |
+LL |         1.0 => {}
+   |         ^^^
+   |
+   = note: `#[warn(illegal_floating_point_literal_pattern)]` on by default
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #41620 <https://github.com/rust-lang/rust/issues/41620>
+
+warning: floating-point types cannot be used in patterns
+  --> $DIR/deduplicate-diagnostics-2.rs:11:9
+   |
+LL |         2.0 => {}
+   |         ^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #41620 <https://github.com/rust-lang/rust/issues/41620>
+
+warning: floating-point types cannot be used in patterns
+  --> $DIR/deduplicate-diagnostics-2.rs:7:9
+   |
+LL |         1.0 => {}
+   |         ^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #41620 <https://github.com/rust-lang/rust/issues/41620>
+
+warning: floating-point types cannot be used in patterns
+  --> $DIR/deduplicate-diagnostics-2.rs:11:9
+   |
+LL |         2.0 => {}
+   |         ^^^
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #41620 <https://github.com/rust-lang/rust/issues/41620>
+

src/test/ui/deduplicate-diagnostics-2.rs

@@ -0,0 +1,17 @@
+// build-pass
+// revisions: duplicate deduplicate
+//[deduplicate] compile-flags: -Z deduplicate-diagnostics=yes
+
+fn main() {
+    match 0.0 {
+        1.0 => {} //~ WARNING floating-point types cannot be used in patterns
+                  //~| WARNING this was previously accepted
+                  //~| WARNING floating-point types cannot be used in patterns
+                  //~| WARNING this was previously accepted
+        2.0 => {} //~ WARNING floating-point types cannot be used in patterns
+                  //~| WARNING this was previously accepted
+                  //[duplicate]~| WARNING floating-point types cannot be used in patterns
+                  //[duplicate]~| WARNING this was previously accepted
+        _ => {}
+    }
+}

src/test/ui/deduplicate-diagnostics.deduplicate.stderr

@@ -1,8 +1,15 @@
+error[E0452]: malformed lint attribute input
+  --> $DIR/deduplicate-diagnostics.rs:8:8
+   |
+LL | #[deny("literal")]
+   |        ^^^^^^^^^ bad attribute argument
+
 error: cannot find derive macro `Unresolved` in this scope
   --> $DIR/deduplicate-diagnostics.rs:4:10
    |
 LL | #[derive(Unresolved)]
    |          ^^^^^^^^^^
 
-error: aborting due to previous error
+error: aborting due to 2 previous errors
 
+For more information about this error, try `rustc --explain E0452`.

src/test/ui/deduplicate-diagnostics.duplicate.stderr

@@ -1,3 +1,9 @@
+error[E0452]: malformed lint attribute input
+  --> $DIR/deduplicate-diagnostics.rs:8:8
+   |
+LL | #[deny("literal")]
+   |        ^^^^^^^^^ bad attribute argument
+
 error: cannot find derive macro `Unresolved` in this scope
   --> $DIR/deduplicate-diagnostics.rs:4:10
    |
@@ -10,5 +16,18 @@ error: cannot find derive macro `Unresolved` in this scope
 LL | #[derive(Unresolved)]
    |          ^^^^^^^^^^
 
-error: aborting due to 2 previous errors
+error[E0452]: malformed lint attribute input
+  --> $DIR/deduplicate-diagnostics.rs:8:8
+   |
+LL | #[deny("literal")]
+   |        ^^^^^^^^^ bad attribute argument
+
+error[E0452]: malformed lint attribute input
+  --> $DIR/deduplicate-diagnostics.rs:8:8
+   |
+LL | #[deny("literal")]
+   |        ^^^^^^^^^ bad attribute argument
+
+error: aborting due to 5 previous errors
 
+For more information about this error, try `rustc --explain E0452`.

src/test/ui/deduplicate-diagnostics.rs

@@ -5,4 +5,7 @@
                       //[duplicate]~| ERROR cannot find derive macro `Unresolved` in this scope
 struct S;
 
+#[deny("literal")] //~ ERROR malformed lint attribute input
+                   //[duplicate]~| ERROR malformed lint attribute input
+                   //[duplicate]~| ERROR malformed lint attribute input
 fn main() {}