Rollup merge of #126013 - nnethercote:unreachable_pub, r=Urgau

Add `#[warn(unreachable_pub)]` to a bunch of compiler crates

By default `unreachable_pub` identifies things that need not be `pub` and tells you to make them `pub(crate)`. But sometimes those things don't need any kind of visibility. So they way I did these was to remove the visibility entirely for each thing the lint identifies, and then add `pub(crate)` back in everywhere the compiler said it was necessary. (Or occasionally `pub(super)` when context suggested that was appropriate.) Tedious, but results in more `pub` removal.

There are plenty more crates to do but this seems like enough for a first PR.

r? `@compiler-errors`

4 files changed, 19 insertions, 21 deletions

diff --git a/compiler/rustc_codegen_llvm/src/back/archive.rs b/compiler/rustc_codegen_llvm/src/back/archive.rs
index c0ec4f86b4d..4f2c83634a8 100644
--- a/compiler/rustc_codegen_llvm/src/back/archive.rs
+++ b/compiler/rustc_codegen_llvm/src/back/archive.rs
@@ -86,7 +86,7 @@ impl<'a> ArchiveBuilder for LlvmArchiveBuilder<'a> {
     }
 }
 
-pub struct LlvmArchiveBuilderBuilder;
+pub(crate) struct LlvmArchiveBuilderBuilder;
 
 impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
     fn new_archive_builder<'a>(&self, sess: &'a Session) -> Box<dyn ArchiveBuilder + 'a> {
diff --git a/compiler/rustc_codegen_llvm/src/back/lto.rs b/compiler/rustc_codegen_llvm/src/back/lto.rs
index aac446f3149..aa6842c75ce 100644
--- a/compiler/rustc_codegen_llvm/src/back/lto.rs
+++ b/compiler/rustc_codegen_llvm/src/back/lto.rs
@@ -33,9 +33,9 @@ use crate::{LlvmCodegenBackend, ModuleLlvm};
 
 /// We keep track of the computed LTO cache keys from the previous
 /// session to determine which CGUs we can reuse.
-pub const THIN_LTO_KEYS_INCR_COMP_FILE_NAME: &str = "thin-lto-past-keys.bin";
+const THIN_LTO_KEYS_INCR_COMP_FILE_NAME: &str = "thin-lto-past-keys.bin";
 
-pub fn crate_type_allows_lto(crate_type: CrateType) -> bool {
+fn crate_type_allows_lto(crate_type: CrateType) -> bool {
     match crate_type {
         CrateType::Executable
         | CrateType::Dylib
@@ -710,7 +710,7 @@ impl Drop for ThinBuffer {
     }
 }
 
-pub unsafe fn optimize_thin_module(
+pub(crate) unsafe fn optimize_thin_module(
     thin_module: ThinModule<LlvmCodegenBackend>,
     cgcx: &CodegenContext<LlvmCodegenBackend>,
 ) -> Result<ModuleCodegen<ModuleLlvm>, FatalError> {
@@ -806,7 +806,7 @@ pub unsafe fn optimize_thin_module(
 
 /// Maps LLVM module identifiers to their corresponding LLVM LTO cache keys
 #[derive(Debug, Default)]
-pub struct ThinLTOKeysMap {
+struct ThinLTOKeysMap {
     // key = llvm name of importing module, value = LLVM cache key
     keys: BTreeMap<String, String>,
 }
@@ -863,7 +863,7 @@ fn module_name_to_str(c_str: &CStr) -> &str {
     })
 }
 
-pub fn parse_module<'a>(
+pub(crate) fn parse_module<'a>(
     cx: &'a llvm::Context,
     name: &CStr,
     data: &[u8],
diff --git a/compiler/rustc_codegen_llvm/src/back/profiling.rs b/compiler/rustc_codegen_llvm/src/back/profiling.rs
index 26fb4a96f84..79794775b7b 100644
--- a/compiler/rustc_codegen_llvm/src/back/profiling.rs
+++ b/compiler/rustc_codegen_llvm/src/back/profiling.rs
@@ -21,14 +21,14 @@ fn llvm_args_to_string_id(profiler: &SelfProfiler, pass_name: &str, ir_name: &st
     EventId::from_label(profiler.alloc_string(components.as_slice()))
 }
 
-pub struct LlvmSelfProfiler<'a> {
+pub(crate) struct LlvmSelfProfiler<'a> {
     profiler: Arc<SelfProfiler>,
     stack: Vec<TimingGuard<'a>>,
     llvm_pass_event_kind: StringId,
 }
 
 impl<'a> LlvmSelfProfiler<'a> {
-    pub fn new(profiler: Arc<SelfProfiler>) -> Self {
+    pub(crate) fn new(profiler: Arc<SelfProfiler>) -> Self {
         let llvm_pass_event_kind = profiler.alloc_string("LLVM Pass");
         Self { profiler, stack: Vec::default(), llvm_pass_event_kind }
     }
@@ -43,7 +43,7 @@ impl<'a> LlvmSelfProfiler<'a> {
     }
 }
 
-pub unsafe extern "C" fn selfprofile_before_pass_callback(
+pub(crate) unsafe extern "C" fn selfprofile_before_pass_callback(
     llvm_self_profiler: *mut c_void,
     pass_name: *const c_char,
     ir_name: *const c_char,
@@ -56,7 +56,7 @@ pub unsafe extern "C" fn selfprofile_before_pass_callback(
     }
 }
 
-pub unsafe extern "C" fn selfprofile_after_pass_callback(llvm_self_profiler: *mut c_void) {
+pub(crate) unsafe extern "C" fn selfprofile_after_pass_callback(llvm_self_profiler: *mut c_void) {
     let llvm_self_profiler = unsafe { &mut *(llvm_self_profiler as *mut LlvmSelfProfiler<'_>) };
     llvm_self_profiler.after_pass_callback();
 }
diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 51b02891d02..adf7e933f43 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -43,14 +43,14 @@ use crate::llvm::{self, DiagnosticInfo, PassManager};
 use crate::type_::Type;
 use crate::{base, common, llvm_util, LlvmCodegenBackend, ModuleLlvm};
 
-pub fn llvm_err<'a>(dcx: DiagCtxtHandle<'_>, err: LlvmError<'a>) -> FatalError {
+pub(crate) fn llvm_err<'a>(dcx: DiagCtxtHandle<'_>, err: LlvmError<'a>) -> FatalError {
     match llvm::last_error() {
         Some(llvm_err) => dcx.emit_almost_fatal(WithLlvmError(err, llvm_err)),
         None => dcx.emit_almost_fatal(err),
     }
 }
 
-pub fn write_output_file<'ll>(
+fn write_output_file<'ll>(
     dcx: DiagCtxtHandle<'_>,
     target: &'ll llvm::TargetMachine,
     pm: &llvm::PassManager<'ll>,
@@ -95,7 +95,7 @@ pub fn write_output_file<'ll>(
     }
 }
 
-pub fn create_informational_target_machine(
+pub(crate) fn create_informational_target_machine(
     sess: &Session,
     only_base_features: bool,
 ) -> OwnedTargetMachine {
@@ -107,7 +107,7 @@ pub fn create_informational_target_machine(
         .unwrap_or_else(|err| llvm_err(sess.dcx(), err).raise())
 }
 
-pub fn create_target_machine(tcx: TyCtxt<'_>, mod_name: &str) -> OwnedTargetMachine {
+pub(crate) fn create_target_machine(tcx: TyCtxt<'_>, mod_name: &str) -> OwnedTargetMachine {
     let split_dwarf_file = if tcx.sess.target_can_use_split_dwarf() {
         tcx.output_filenames(()).split_dwarf_path(
             tcx.sess.split_debuginfo(),
@@ -130,9 +130,7 @@ pub fn create_target_machine(tcx: TyCtxt<'_>, mod_name: &str) -> OwnedTargetMach
     .unwrap_or_else(|err| llvm_err(tcx.dcx(), err).raise())
 }
 
-pub fn to_llvm_opt_settings(
-    cfg: config::OptLevel,
-) -> (llvm::CodeGenOptLevel, llvm::CodeGenOptSize) {
+fn to_llvm_opt_settings(cfg: config::OptLevel) -> (llvm::CodeGenOptLevel, llvm::CodeGenOptSize) {
     use self::config::OptLevel::*;
     match cfg {
         No => (llvm::CodeGenOptLevel::None, llvm::CodeGenOptSizeNone),
@@ -179,7 +177,7 @@ pub(crate) fn to_llvm_code_model(code_model: Option<CodeModel>) -> llvm::CodeMod
     }
 }
 
-pub fn target_machine_factory(
+pub(crate) fn target_machine_factory(
     sess: &Session,
     optlvl: config::OptLevel,
     target_features: &[String],
@@ -320,7 +318,7 @@ pub(crate) fn save_temp_bitcode(
 }
 
 /// In what context is a dignostic handler being attached to a codegen unit?
-pub enum CodegenDiagnosticsStage {
+pub(crate) enum CodegenDiagnosticsStage {
     /// Prelink optimization stage.
     Opt,
     /// LTO/ThinLTO postlink optimization stage.
@@ -329,14 +327,14 @@ pub enum CodegenDiagnosticsStage {
     Codegen,
 }
 
-pub struct DiagnosticHandlers<'a> {
+pub(crate) struct DiagnosticHandlers<'a> {
     data: *mut (&'a CodegenContext<LlvmCodegenBackend>, DiagCtxtHandle<'a>),
     llcx: &'a llvm::Context,
     old_handler: Option<&'a llvm::DiagnosticHandler>,
 }
 
 impl<'a> DiagnosticHandlers<'a> {
-    pub fn new(
+    pub(crate) fn new(
         cgcx: &'a CodegenContext<LlvmCodegenBackend>,
         dcx: DiagCtxtHandle<'a>,
         llcx: &'a llvm::Context,