Small ty::print cleanups

compiler/rustc_middle/src/ty/print/mod.rs

@@ -12,8 +12,6 @@ pub use self::pretty::*;
 
 pub type PrintError = std::fmt::Error;
 
-// FIXME(eddyb) false positive, the lifetime parameters are used with `P:  Printer<...>`.
-#[allow(unused_lifetimes)]
 pub trait Print<'tcx, P> {
     fn print(&self, cx: &mut P) -> Result<(), PrintError>;
 }

compiler/rustc_middle/src/ty/print/pretty.rs

@@ -53,7 +53,6 @@ macro_rules! p {
 }
 macro_rules! define_scoped_cx {
     ($cx:ident) => {
-        #[allow(unused_macros)]
         macro_rules! scoped_cx {
             () => {
                 $cx
@@ -408,8 +407,6 @@ pub trait PrettyPrinter<'tcx>: Printer<'tcx> + fmt::Write {
         def_id: DefId,
         callers: &mut Vec<DefId>,
     ) -> Result<bool, PrintError> {
-        define_scoped_cx!(self);
-
         debug!("try_print_visible_def_path: def_id={:?}", def_id);
 
         // If `def_id` is a direct or injected extern crate, return the
@@ -1868,8 +1865,6 @@ impl<'tcx> Printer<'tcx> for FmtPrinter<'_, 'tcx> {
         def_id: DefId,
         args: &'tcx [GenericArg<'tcx>],
     ) -> Result<(), PrintError> {
-        define_scoped_cx!(self);
-
         if args.is_empty() {
             match self.try_print_trimmed_def_path(def_id)? {
                 true => return Ok(()),
@@ -2401,8 +2396,6 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
             let _ = write!(cx, "{cont}");
         };
 
-        define_scoped_cx!(self);
-
         let possible_names = ('a'..='z').rev().map(|s| Symbol::intern(&format!("'{s}")));
 
         let mut available_names = possible_names
@@ -2630,46 +2623,6 @@ where
     }
 }
 
-macro_rules! forward_display_to_print {
-    ($($ty:ty),+) => {
-        // Some of the $ty arguments may not actually use 'tcx
-        $(#[allow(unused_lifetimes)] impl<'tcx> fmt::Display for $ty {
-            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-                ty::tls::with(|tcx| {
-                    let mut cx = FmtPrinter::new(tcx, Namespace::TypeNS);
-                    tcx.lift(*self)
-                        .expect("could not lift for printing")
-                        .print(&mut cx)?;
-                    f.write_str(&cx.into_buffer())?;
-                    Ok(())
-                })
-            }
-        })+
-    };
-}
-
-macro_rules! define_print_and_forward_display {
-    (($self:ident, $cx:ident): $($ty:ty $print:block)+) => {
-        define_print!(($self, $cx): $($ty $print)*);
-        forward_display_to_print!($($ty),+);
-    };
-}
-
-macro_rules! define_print {
-    (($self:ident, $cx:ident): $($ty:ty $print:block)+) => {
-        $(impl<'tcx, P: PrettyPrinter<'tcx>> Print<'tcx, P> for $ty {
-            fn print(&$self, $cx: &mut P) -> Result<(), PrintError> {
-                #[allow(unused_mut)]
-                let mut $cx = $cx;
-                define_scoped_cx!($cx);
-                let _: () = $print;
-                #[allow(unreachable_code)]
-                Ok(())
-            }
-        })+
-    };
-}
-
 /// Wrapper type for `ty::TraitRef` which opts-in to pretty printing only
 /// the trait path. That is, it will print `Trait<U>` instead of
 /// `<T as Trait<U>>`.
@@ -2744,6 +2697,43 @@ pub struct PrintClosureAsImpl<'tcx> {
     pub closure: ty::ClosureArgs<'tcx>,
 }
 
+macro_rules! forward_display_to_print {
+    ($($ty:ty),+) => {
+        // Some of the $ty arguments may not actually use 'tcx
+        $(#[allow(unused_lifetimes)] impl<'tcx> fmt::Display for $ty {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+                ty::tls::with(|tcx| {
+                    let mut cx = FmtPrinter::new(tcx, Namespace::TypeNS);
+                    tcx.lift(*self)
+                        .expect("could not lift for printing")
+                        .print(&mut cx)?;
+                    f.write_str(&cx.into_buffer())?;
+                    Ok(())
+                })
+            }
+        })+
+    };
+}
+
+macro_rules! define_print {
+    (($self:ident, $cx:ident): $($ty:ty $print:block)+) => {
+        $(impl<'tcx, P: PrettyPrinter<'tcx>> Print<'tcx, P> for $ty {
+            fn print(&$self, $cx: &mut P) -> Result<(), PrintError> {
+                define_scoped_cx!($cx);
+                let _: () = $print;
+                Ok(())
+            }
+        })+
+    };
+}
+
+macro_rules! define_print_and_forward_display {
+    (($self:ident, $cx:ident): $($ty:ty $print:block)+) => {
+        define_print!(($self, $cx): $($ty $print)*);
+        forward_display_to_print!($($ty),+);
+    };
+}
+
 forward_display_to_print! {
     ty::Region<'tcx>,
     Ty<'tcx>,