Auto merge of #142483 - workingjubilee:rollup-8qnhueh, r=workingjubilee

Rollup of 16 pull requests

Successful merges:

 - rust-lang/rust#140969 (Allow initializing logger with additional tracing Layer)
 - rust-lang/rust#141352 (builtin dyn impl no guide inference)
 - rust-lang/rust#142046 (add Vec::peek_mut)
 - rust-lang/rust#142273 (tests: Minicore `extern "gpu-kernel"` feature test)
 - rust-lang/rust#142302 (Rework how the disallowed qualifier in function type diagnostics are generated)
 - rust-lang/rust#142405 (Don't hardcode the intrinsic return types twice in the compiler)
 - rust-lang/rust#142434 ( Pre-install JS dependencies in tidy Dockerfile)
 - rust-lang/rust#142439 (doc: mention that intrinsics should not be called in user code)
 - rust-lang/rust#142441 (Delay replacing escaping bound vars in `FindParamInClause`)
 - rust-lang/rust#142449 (Require generic params for const generic params)
 - rust-lang/rust#142452 (Remove "intermittent" wording from `ReadDir`)
 - rust-lang/rust#142459 (Remove output helper bootstrap)
 - rust-lang/rust#142460 (cleanup search graph impl)
 - rust-lang/rust#142461 (compiletest: Clarify that `--no-capture` is needed with `--verbose`)
 - rust-lang/rust#142475 (Add platform support docs & maintainers for *-windows-msvc)
 - rust-lang/rust#142480 (tests: Convert two handwritten minicores to add-core-stubs)

r? `@ghost`
`@rustbot` modify labels: rollup

1 files changed, 32 insertions, 1 deletions

diff --git a/compiler/rustc_log/src/lib.rs b/compiler/rustc_log/src/lib.rs
index 1bb502ca3d0..df648bbd489 100644
--- a/compiler/rustc_log/src/lib.rs
+++ b/compiler/rustc_log/src/lib.rs
@@ -43,6 +43,7 @@ use tracing_subscriber::filter::{Directive, EnvFilter, LevelFilter};
 use tracing_subscriber::fmt::FmtContext;
 use tracing_subscriber::fmt::format::{self, FormatEvent, FormatFields};
 use tracing_subscriber::layer::SubscriberExt;
+use tracing_subscriber::{Layer, Registry};
 
 /// The values of all the environment variables that matter for configuring a logger.
 /// Errors are explicitly preserved so that we can share error handling.
@@ -72,6 +73,36 @@ impl LoggerConfig {
 
 /// Initialize the logger with the given values for the filter, coloring, and other options env variables.
 pub fn init_logger(cfg: LoggerConfig) -> Result<(), Error> {
+    init_logger_with_additional_layer(cfg, || Registry::default())
+}
+
+/// Trait alias for the complex return type of `build_subscriber` in
+/// [init_logger_with_additional_layer]. A [Registry] with any composition of [tracing::Subscriber]s
+/// (e.g. `Registry::default().with(custom_layer)`) should be compatible with this type.
+/// Having an alias is also useful so rustc_driver_impl does not need to explicitly depend on
+/// `tracing_subscriber`.
+pub trait BuildSubscriberRet:
+    tracing::Subscriber + for<'span> tracing_subscriber::registry::LookupSpan<'span> + Send + Sync
+{
+}
+
+impl<
+    T: tracing::Subscriber + for<'span> tracing_subscriber::registry::LookupSpan<'span> + Send + Sync,
+> BuildSubscriberRet for T
+{
+}
+
+/// Initialize the logger with the given values for the filter, coloring, and other options env variables.
+/// Additionally add a custom layer to collect logging and tracing events via `build_subscriber`,
+/// for example: `|| Registry::default().with(custom_layer)`.
+pub fn init_logger_with_additional_layer<F, T>(
+    cfg: LoggerConfig,
+    build_subscriber: F,
+) -> Result<(), Error>
+where
+    F: FnOnce() -> T,
+    T: BuildSubscriberRet,
+{
     let filter = match cfg.filter {
         Ok(env) => EnvFilter::new(env),
         _ => EnvFilter::default().add_directive(Directive::from(LevelFilter::WARN)),
@@ -124,7 +155,7 @@ pub fn init_logger(cfg: LoggerConfig) -> Result<(), Error> {
         Err(_) => {} // no wraptree
     }
 
-    let subscriber = tracing_subscriber::Registry::default().with(filter).with(layer);
+    let subscriber = build_subscriber().with(layer.with_filter(filter));
     match cfg.backtrace {
         Ok(backtrace_target) => {
             let fmt_layer = tracing_subscriber::fmt::layer()