Add warn(unreachable_pub) to rustc_passes.

Author: nnethercote

compiler/rustc_passes/src/debugger_visualizer.rs

@@ -95,6 +95,6 @@ fn debugger_visualizers(tcx: TyCtxt<'_>, _: LocalCrate) -> Vec<DebuggerVisualize
     visitor.visualizers
 }
 
-pub fn provide(providers: &mut Providers) {
+pub(crate) fn provide(providers: &mut Providers) {
     providers.debugger_visualizers = debugger_visualizers;
 }

compiler/rustc_passes/src/diagnostic_items.rs

@@ -90,7 +90,7 @@ fn all_diagnostic_items(tcx: TyCtxt<'_>, (): ()) -> DiagnosticItems {
     items
 }
 
-pub fn provide(providers: &mut Providers) {
+pub(crate) fn provide(providers: &mut Providers) {
     providers.diagnostic_items = diagnostic_items;
     providers.all_diagnostic_items = all_diagnostic_items;
 }