Add test

src/test/ui/suggestions/dont-suggest-deref-inside-macro-issue-58298.rs

@@ -0,0 +1,14 @@
+fn warn(_: &str) {}
+
+macro_rules! intrinsic_match {
+    ($intrinsic:expr) => {
+        warn(format!("unsupported intrinsic {}", $intrinsic));
+        //^~ ERROR mismatched types
+    };
+}
+
+fn main() {
+    intrinsic_match! {
+        "abc"
+    };
+}

src/test/ui/suggestions/dont-suggest-deref-inside-macro-issue-58298.stderr

@@ -0,0 +1,21 @@
+error[E0308]: mismatched types
+  --> $DIR/dont-suggest-deref-inside-macro-issue-58298.rs:10:5
+   |
+LL |        intrinsic_match! {
+   |   _____^
+   |  |_____|
+   | ||
+LL | ||         "abc"
+LL | ||     };
+   | ||      ^
+   | ||______|
+   | |_______expected &str, found struct `std::string::String`
+   |         in this macro invocation
+   |
+   = note: expected type `&str`
+              found type `std::string::String`
+   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.