Structured suggestion for missing mut/const in pointer

5 files changed, 38 insertions, 8 deletions

diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs
index b47f0c09783..2a8512acf8c 100644
--- a/compiler/rustc_parse/src/parser/ty.rs
+++ b/compiler/rustc_parse/src/parser/ty.rs
@@ -397,10 +397,13 @@ impl<'a> Parser<'a> {
     fn parse_ty_ptr(&mut self) -> PResult<'a, TyKind> {
         let mutbl = self.parse_const_or_mut().unwrap_or_else(|| {
             let span = self.prev_token.span;
-            let msg = "expected mut or const in raw pointer type";
-            self.struct_span_err(span, msg)
-                .span_label(span, msg)
-                .help("use `*mut T` or `*const T` as appropriate")
+            self.struct_span_err(span, "expected `mut` or `const` keyword in raw pointer type")
+                .span_suggestions(
+                    span.shrink_to_hi(),
+                    "add `mut` or `const` here",
+                    ["mut ".to_string(), "const ".to_string()].into_iter(),
+                    Applicability::HasPlaceholders,
+                )
                 .emit();
             Mutability::Not
         });
diff --git a/src/test/ui/parser/bad-pointer-type.rs b/src/test/ui/parser/bad-pointer-type.rs
index 59e5e0c5d31..6a82acb4cd6 100644
--- a/src/test/ui/parser/bad-pointer-type.rs
+++ b/src/test/ui/parser/bad-pointer-type.rs
@@ -1,5 +1,5 @@
 fn foo(_: *()) {
-    //~^ ERROR expected mut or const in raw pointer type
+    //~^ ERROR expected `mut` or `const` keyword in raw pointer type
 }
 
 fn main() {}
diff --git a/src/test/ui/parser/bad-pointer-type.stderr b/src/test/ui/parser/bad-pointer-type.stderr
index e18c220affe..b7225ca887d 100644
--- a/src/test/ui/parser/bad-pointer-type.stderr
+++ b/src/test/ui/parser/bad-pointer-type.stderr
@@ -1,10 +1,15 @@
-error: expected mut or const in raw pointer type
+error: expected `mut` or `const` keyword in raw pointer type
   --> $DIR/bad-pointer-type.rs:1:11
    |
 LL | fn foo(_: *()) {
-   |           ^ expected mut or const in raw pointer type
+   |           ^
    |
-   = help: use `*mut T` or `*const T` as appropriate
+help: add `mut` or `const` here
+   |
+LL | fn foo(_: *const ()) {
+   |            +++++
+LL | fn foo(_: *mut ()) {
+   |            +++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/parser/double-pointer.rs b/src/test/ui/parser/double-pointer.rs
new file mode 100644
index 00000000000..54d34db4a50
--- /dev/null
+++ b/src/test/ui/parser/double-pointer.rs
@@ -0,0 +1,7 @@
+fn main() {
+    let x: i32 = 5;
+    let ptr: *const i32 = &x;
+    let dptr: **const i32 = &ptr;
+    //~^ ERROR expected `mut` or `const` keyword in raw pointer type
+    //~| HELP add `mut` or `const` here
+}
diff --git a/src/test/ui/parser/double-pointer.stderr b/src/test/ui/parser/double-pointer.stderr
new file mode 100644
index 00000000000..28037f93265
--- /dev/null
+++ b/src/test/ui/parser/double-pointer.stderr
@@ -0,0 +1,15 @@
+error: expected `mut` or `const` keyword in raw pointer type
+  --> $DIR/double-pointer.rs:4:15
+   |
+LL |     let dptr: **const i32 = &ptr;
+   |               ^
+   |
+help: add `mut` or `const` here
+   |
+LL |     let dptr: *const *const i32 = &ptr;
+   |                +++++
+LL |     let dptr: *mut *const i32 = &ptr;
+   |                +++
+
+error: aborting due to previous error
+