Stop telling people to submit bugs for internal feature ICEs

This keeps track of usage of internal features, and changes the message
to instead tell them that using internal features is not supported.

See MCP 620.

Author: Noratrieb

compiler/rustc_driver_impl/messages.ftl

@@ -1,5 +1,6 @@
 driver_impl_ice = the compiler unexpectedly panicked. this is a bug.
 driver_impl_ice_bug_report = we would appreciate a bug report: {$bug_report_url}
+driver_impl_ice_bug_report_internal_feature = using internal features is not supported and is expected to lead to internal compiler errors
 driver_impl_ice_exclude_cargo_defaults = some of the compiler flags provided by cargo are hidden
 
 driver_impl_ice_flags = compiler flags: {$flags}

compiler/rustc_driver_impl/src/lib.rs

@@ -60,7 +60,7 @@ use std::path::PathBuf;
 use std::process::{self, Command, Stdio};
 use std::str;
 use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::OnceLock;
+use std::sync::{Arc, OnceLock};
 use std::time::{Instant, SystemTime};
 use time::format_description::well_known::Rfc3339;
 use time::OffsetDateTime;
@@ -224,11 +224,18 @@ pub struct RunCompiler<'a, 'b> {
     file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
     make_codegen_backend:
         Option<Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>>,
+    using_internal_features: Option<Arc<std::sync::atomic::AtomicBool>>,
 }
 
 impl<'a, 'b> RunCompiler<'a, 'b> {
     pub fn new(at_args: &'a [String], callbacks: &'b mut (dyn Callbacks + Send)) -> Self {
-        Self { at_args, callbacks, file_loader: None, make_codegen_backend: None }
+        Self {
+            at_args,
+            callbacks,
+            file_loader: None,
+            make_codegen_backend: None,
+            using_internal_features: None,
+        }
     }
 
     /// Set a custom codegen backend.
@@ -260,9 +267,25 @@ impl<'a, 'b> RunCompiler<'a, 'b> {
         self
     }
 
+    /// Set the session-global flag that checks whether internal features have been used,
+    /// suppressing the message about submitting an issue in ICEs when enabled.
+    pub fn set_using_internal_features(
+        &mut self,
+        using_internal_features: Option<Arc<AtomicBool>>,
+    ) -> &mut Self {
+        self.using_internal_features = using_internal_features;
+        self
+    }
+
     /// Parse args and run the compiler.
     pub fn run(self) -> interface::Result<()> {
-        run_compiler(self.at_args, self.callbacks, self.file_loader, self.make_codegen_backend)
+        run_compiler(
+            self.at_args,
+            self.callbacks,
+            self.file_loader,
+            self.make_codegen_backend,
+            self.using_internal_features,
+        )
     }
 }
 
@@ -273,6 +296,7 @@ fn run_compiler(
     make_codegen_backend: Option<
         Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>,
     >,
+    using_internal_features: Option<Arc<std::sync::atomic::AtomicBool>>,
 ) -> interface::Result<()> {
     let mut early_error_handler = EarlyErrorHandler::new(ErrorOutputType::default());
 
@@ -316,6 +340,7 @@ fn run_compiler(
         override_queries: None,
         make_codegen_backend,
         registry: diagnostics_registry(),
+        using_internal_features,
         expanded_args: args,
     };
 
@@ -1323,8 +1348,16 @@ fn ice_path() -> &'static Option<PathBuf> {
 /// If you have no extra info to report, pass the empty closure `|_| ()` as the argument to
 /// extra_info.
 ///
+/// If emitting the "please submit a bug" message is fine when internal features are enabled, `None`
+/// can be passed as the `using_internal_features`. To hide the note, pass in a bool that is also passed
+/// to [`RunCompiler::set_using_internal_features`].
+///
 /// A custom rustc driver can skip calling this to set up a custom ICE hook.
-pub fn install_ice_hook(bug_report_url: &'static str, extra_info: fn(&Handler)) {
+pub fn install_ice_hook(
+    bug_report_url: &'static str,
+    extra_info: fn(&Handler),
+    using_internal_features: Option<Arc<AtomicBool>>,
+) {
     // If the user has not explicitly overridden "RUST_BACKTRACE", then produce
     // full backtraces. When a compiler ICE happens, we want to gather
     // as much information as possible to present in the issue opened
@@ -1384,7 +1417,7 @@ pub fn install_ice_hook(bug_report_url: &'static str, extra_info: fn(&Handler))
             }
 
             // Print the ICE message
-            report_ice(info, bug_report_url, extra_info);
+            report_ice(info, bug_report_url, extra_info, using_internal_features.clone());
         },
     ));
 }
@@ -1395,7 +1428,12 @@ pub fn install_ice_hook(bug_report_url: &'static str, extra_info: fn(&Handler))
 ///
 /// When `install_ice_hook` is called, this function will be called as the panic
 /// hook.
-fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str, extra_info: fn(&Handler)) {
+fn report_ice(
+    info: &panic::PanicInfo<'_>,
+    bug_report_url: &str,
+    extra_info: fn(&Handler),
+    using_internal_features: Option<Arc<AtomicBool>>,
+) {
     let fallback_bundle =
         rustc_errors::fallback_fluent_bundle(crate::DEFAULT_LOCALE_RESOURCES.to_vec(), false);
     let emitter = Box::new(rustc_errors::emitter::EmitterWriter::stderr(
@@ -1412,7 +1450,13 @@ fn report_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str, extra_info: fn(
         handler.emit_err(session_diagnostics::Ice);
     }
 
-    handler.emit_note(session_diagnostics::IceBugReport { bug_report_url });
+    if using_internal_features
+        .map_or(false, |internal| internal.load(std::sync::atomic::Ordering::Relaxed))
+    {
+        handler.emit_note(session_diagnostics::IceBugReportInternalFeature);
+    } else {
+        handler.emit_note(session_diagnostics::IceBugReport { bug_report_url });
+    }
 
     let version = util::version_str!().unwrap_or("unknown_version");
     let triple = config::host_triple();
@@ -1493,10 +1537,12 @@ pub fn main() -> ! {
 
     let handler = EarlyErrorHandler::new(ErrorOutputType::default());
 
+    let using_internal_features = Some(Arc::default());
+
     init_rustc_env_logger(&handler);
     signal_handler::install();
     let mut callbacks = TimePassesCallbacks::default();
-    install_ice_hook(DEFAULT_BUG_REPORT_URL, |_| ());
+    install_ice_hook(DEFAULT_BUG_REPORT_URL, |_| (), using_internal_features.clone());
     let exit_code = catch_with_exit_code(|| {
         let args = env::args_os()
             .enumerate()
@@ -1506,7 +1552,9 @@ pub fn main() -> ! {
                 })
             })
             .collect::<Vec<_>>();
-        RunCompiler::new(&args, &mut callbacks).run()
+        let mut run = RunCompiler::new(&args, &mut callbacks);
+        run.set_using_internal_features(using_internal_features);
+        run.run()
     });
 
     if let Some(format) = callbacks.time_passes {

compiler/rustc_driver_impl/src/session_diagnostics.rs

@@ -42,6 +42,10 @@ pub(crate) struct IceBugReport<'a> {
     pub bug_report_url: &'a str,
 }
 
+#[derive(Diagnostic)]
+#[diag(driver_impl_ice_bug_report_internal_feature)]
+pub(crate) struct IceBugReportInternalFeature;
+
 #[derive(Diagnostic)]
 #[diag(driver_impl_ice_version)]
 pub(crate) struct IceVersion<'a> {

compiler/rustc_expand/src/config.rs

@@ -167,6 +167,11 @@ pub fn features(sess: &Session, krate_attrs: &[Attribute]) -> Features {
             // If the declared feature is unstable, record it.
             if let Some(f) = UNSTABLE_FEATURES.iter().find(|f| name == f.feature.name) {
                 (f.set_enabled)(&mut features);
+                if features.internal(name) {
+                    if let Some(using_internal_features) = &sess.using_internal_features {
+                        using_internal_features.store(true, std::sync::atomic::Ordering::Relaxed);
+                    }
+                }
                 features.set_declared_lang_feature(name, mi.span(), None);
                 continue;
             }

compiler/rustc_interface/src/interface.rs

@@ -23,6 +23,7 @@ use rustc_span::source_map::{FileLoader, FileName};
 use rustc_span::symbol::sym;
 use std::path::PathBuf;
 use std::result;
+use std::sync::Arc;
 
 pub type Result<T> = result::Result<T, ErrorGuaranteed>;
 
@@ -280,6 +281,11 @@ pub struct Config {
     /// Registry of diagnostics codes.
     pub registry: Registry,
 
+    /// Enabled when a feature marked as `internal` is enabled. Makes it so that
+    /// "please report a bug" is hidden, as ICEs with internal features are wontfix,
+    /// and they are usually the cause of the ICEs.
+    pub using_internal_features: Option<Arc<std::sync::atomic::AtomicBool>>,
+
     /// All commandline args used to invoke the compiler, with @file args fully expanded.
     /// This will only be used within debug info, e.g. in the pdb file on windows
     /// This is mainly useful for other tools that reads that debuginfo to figure out
@@ -323,6 +329,7 @@ pub fn run_compiler<R: Send>(config: Config, f: impl FnOnce(&Compiler) -> R + Se
                 config.make_codegen_backend,
                 registry.clone(),
                 config.ice_file,
+                config.using_internal_features,
                 config.expanded_args,
             );
 

compiler/rustc_interface/src/tests.rs

@@ -69,6 +69,7 @@ fn mk_session(handler: &mut EarlyErrorHandler, matches: getopts::Matches) -> (Se
         None,
         "",
         None,
+        None,
         Default::default(),
     );
     (sess, cfg)

compiler/rustc_interface/src/util.rs

@@ -26,7 +26,7 @@ use std::env::consts::{DLL_PREFIX, DLL_SUFFIX};
 use std::mem;
 use std::path::{Path, PathBuf};
 use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::OnceLock;
+use std::sync::{Arc, OnceLock};
 use std::thread;
 
 /// Function pointer type that constructs a new CodegenBackend.
@@ -71,6 +71,7 @@ pub fn create_session(
     >,
     descriptions: Registry,
     ice_file: Option<PathBuf>,
+    using_internal_features: Option<Arc<AtomicBool>>,
     expanded_args: Vec<String>,
 ) -> (Session, Box<dyn CodegenBackend>) {
     let codegen_backend = if let Some(make_codegen_backend) = make_codegen_backend {
@@ -114,6 +115,7 @@ pub fn create_session(
         target_override,
         rustc_version_str().unwrap_or("unknown"),
         ice_file,
+        using_internal_features,
         expanded_args,
     );
 

compiler/rustc_session/src/session.rs

@@ -44,7 +44,7 @@ use std::fmt;
 use std::ops::{Div, Mul};
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
-use std::sync::Arc;
+use std::sync::{atomic::AtomicBool, Arc};
 use std::time::Duration;
 
 pub struct OptimizationFuel {
@@ -201,6 +201,11 @@ pub struct Session {
     /// The version of the rustc process, possibly including a commit hash and description.
     pub cfg_version: &'static str,
 
+    /// Enabled when a feature marked as `internal` is enabled. Makes it so that
+    /// "please report a bug" is hidden, as ICEs with internal features are wontfix,
+    /// and they are usually the cause of the ICEs.
+    pub using_internal_features: Option<Arc<AtomicBool>>,
+
     /// All commandline args used to invoke the compiler, with @file args fully expanded.
     /// This will only be used within debug info, e.g. in the pdb file on windows
     /// This is mainly useful for other tools that reads that debuginfo to figure out
@@ -1333,6 +1338,7 @@ pub fn build_session(
     target_override: Option<Target>,
     cfg_version: &'static str,
     ice_file: Option<PathBuf>,
+    using_internal_features: Option<Arc<AtomicBool>>,
     expanded_args: Vec<String>,
 ) -> Session {
     // FIXME: This is not general enough to make the warning lint completely override
@@ -1469,6 +1475,7 @@ pub fn build_session(
         target_features: Default::default(),
         unstable_target_features: Default::default(),
         cfg_version,
+        using_internal_features,
         expanded_args,
     };
 

src/librustdoc/core.rs

@@ -292,6 +292,7 @@ pub(crate) fn create_config(
         make_codegen_backend: None,
         registry: rustc_driver::diagnostics_registry(),
         ice_file: None,
+        using_internal_features: None,
         expanded_args,
     }
 }

src/librustdoc/doctest.rs

@@ -109,6 +109,7 @@ pub(crate) fn run(options: RustdocOptions) -> Result<(), ErrorGuaranteed> {
         make_codegen_backend: None,
         registry: rustc_driver::diagnostics_registry(),
         ice_file: None,
+        using_internal_features: None,
         expanded_args: options.expanded_args.clone(),
     };