Merge ref 'c5dabe8cf798' from rust-lang/rust

Pull recent changes from https://github.com/rust-lang/rust via Josh.

Upstream ref: c5dabe8cf798123087d094f06417f5a767ca73e8
Filtered ref: 3214048a4d271548c85aae8ffc5f28ec73719235
Upstream diff: rust-lang/rust@fb24b04...c5dabe8

This merge was created using https://github.com/rust-lang/josh-sync.

Author: The rustc-josh-sync Cronjob Bot

.github/workflows/ci.yml

@@ -31,7 +31,8 @@ jobs:
             os: ubuntu-24.04-arm
             multiarch: armhf
             gcc_cross: arm-linux-gnueabihf
-          # Disabled due to Ubuntu repo trouble
+          # Ubuntu mirrors are not reliable enough for these architectures
+          # (see <https://bugs.launchpad.net/ubuntu/+bug/2130309>).
           # - host_target: riscv64gc-unknown-linux-gnu
           #   os: ubuntu-latest
           #   multiarch: riscv64
@@ -68,7 +69,7 @@ jobs:
       - name: install multiarch
         if: ${{ matrix.multiarch != '' }}
         run: |
-          # s390x, ppc64el, riscv64 need Ubuntu Ports to be in the mirror list
+          # armhf, s390x, ppc64el, riscv64 need Ubuntu Ports to be in the mirror list
           sudo bash -c "echo 'https://ports.ubuntu.com/	priority:4' >> /etc/apt/apt-mirrors.txt"
           # Add architecture
           sudo dpkg --add-architecture ${{ matrix.multiarch }}

Cargo.lock

@@ -39,7 +39,7 @@ features = ['unprefixed_malloc_on_supported_platforms']
 [target.'cfg(unix)'.dependencies]
 libc = "0.2"
 # native-lib dependencies
-libffi = { version = "4.1.1", optional = true }
+libffi = { version = "5.0.0", optional = true }
 libloading = { version = "0.8", optional = true }
 serde = { version = "1.0.219", features = ["derive"], optional = true }
 

Cargo.toml

@@ -292,6 +292,9 @@ Try running `cargo miri clean`.
 Miri adds its own set of `-Z` flags, which are usually set via the `MIRIFLAGS`
 environment variable. We first document the most relevant and most commonly used flags:
 
+* `-Zmiri-backtrace=<0|1|full>` configures how Miri prints backtraces: `1` is the default,
+  where backtraces are printed in pruned form; `full` prints backtraces without pruning, and `0`
+  disables backtraces entirely.
 * `-Zmiri-deterministic-concurrency` makes Miri's concurrency-related behavior fully deterministic.
   Strictly speaking, Miri is always fully deterministic when isolation is enabled (the default
   mode), but this determinism is achieved by using an RNG with a fixed seed. Seemingly harmless
@@ -373,6 +376,12 @@ environment variable. We first document the most relevant and most commonly used
   ensure alignment.  (The standard library `align_to` method works fine in both modes; under
   symbolic alignment it only fills the middle slice when the allocation guarantees sufficient
   alignment.)
+* `-Zmiri-user-relevant-crates=<crate>,<crate>,...` extends the list of crates that Miri considers
+  "user-relevant". This affects the rendering of backtraces (for user-relevant crates, Miri shows
+  not just the function name but the actual code) and it affects the spans collected for data races
+  and aliasing violations (where Miri will show the span of the topmost non-`#[track_caller]` frame
+  in a user-relevant crate). When using `cargo miri`, the crates in the local workspace are always
+  considered user-relevant.
 
 The remaining flags are for advanced use only, and more likely to change or be removed.
 Some of these are **unsound**, which means they can lead
@@ -474,7 +483,8 @@ to Miri failing to detect cases of undefined behavior in a program.
 * `-Zmiri-track-alloc-id=<id1>,<id2>,...` shows a backtrace when the given allocations are
   being allocated or freed.  This helps in debugging memory leaks and
   use after free bugs. Specifying this argument multiple times does not overwrite the previous
-  values, instead it appends its values to the list. Listing an id multiple times has no effect.
+  values, instead it appends its values to the list. Listing an ID multiple times has no effect.
+  You can also add IDs at runtime using `miri_track_alloc`.
 * `-Zmiri-track-pointer-tag=<tag1>,<tag2>,...` shows a backtrace when a given pointer tag
   is created and when (if ever) it is popped from a borrow stack (which is where the tag becomes invalid
   and any future use of it will error).  This helps you in finding out why UB is

README.md

@@ -213,7 +213,11 @@ fn cargo_extra_flags() -> Vec<String> {
 
 pub fn get_cargo_metadata() -> Metadata {
     // This will honor the `CARGO` env var the same way our `cargo()` does.
-    MetadataCommand::new().no_deps().other_options(cargo_extra_flags()).exec().unwrap()
+    MetadataCommand::new()
+        .no_deps()
+        .other_options(cargo_extra_flags())
+        .exec()
+        .unwrap_or_else(|err| show_error!("{}", err))
 }
 
 /// Pulls all the crates in this workspace from the cargo metadata.

cargo-miri/src/util.rs

@@ -1 +1 @@
-36e4f5d1fe1d63953a5bf1758ce2b64172623e2e
+292be5c7c05138d753bbd4b30db7a3f1a5c914f7

rust-version

@@ -2,6 +2,7 @@ use std::env::{self, VarError};
 use std::str::FromStr;
 use std::sync::{Mutex, OnceLock};
 
+use rustc_log::tracing;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::{CtfeBacktrace, EarlyDiagCtxt};
 
@@ -72,8 +73,8 @@ fn init_logger_once(early_dcx: &EarlyDiagCtxt) {
                     early_dcx,
                     rustc_logger_config(),
                     || {
-                        tracing_subscriber::layer::SubscriberExt::with(
-                            tracing_subscriber::Registry::default(),
+                        rustc_log::tracing_subscriber::layer::SubscriberExt::with(
+                            rustc_log::tracing_subscriber::Registry::default(),
                             chrome_layer,
                         )
                     },

src/bin/log/setup.rs

@@ -24,12 +24,9 @@
 #![allow(warnings)]
 #![cfg(feature = "tracing")]
 
-// This is here and not in src/lib.rs since it is a direct dependency of tracing_chrome.rs and
-// should not be included if the "tracing" feature is disabled.
-extern crate tracing_core;
-
-use tracing_core::{field::Field, span, Event, Subscriber};
-use tracing_subscriber::{
+use rustc_log::tracing_core::{field::Field, span, Event, Subscriber};
+use rustc_log::tracing_subscriber::{
+    self,
     layer::Context,
     registry::{LookupSpan, SpanRef},
     Layer,

src/bin/log/tracing_chrome.rs

@@ -8,11 +8,6 @@
     rustc::untranslatable_diagnostic
 )]
 
-// Some "regular" crates we want to share with rustc
-extern crate tracing;
-#[cfg(feature = "tracing")]
-extern crate tracing_subscriber;
-
 // The rustc crates we need
 extern crate rustc_abi;
 extern crate rustc_data_structures;
@@ -48,6 +43,7 @@ use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_hir::{self as hir, Node};
 use rustc_hir_analysis::check::check_function_signature;
 use rustc_interface::interface::Config;
+use rustc_log::tracing::debug;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::middle::exported_symbols::{
     ExportedSymbol, SymbolExportInfo, SymbolExportKind, SymbolExportLevel,
@@ -60,7 +56,6 @@ use rustc_session::EarlyDiagCtxt;
 use rustc_session::config::{CrateType, ErrorOutputType, OptLevel};
 use rustc_session::search_paths::PathKind;
 use rustc_span::def_id::DefId;
-use tracing::debug;
 
 use crate::log::setup::{deinit_loggers, init_early_loggers, init_late_loggers};
 
@@ -715,6 +710,8 @@ fn main() {
                 fatal_error!("-Zmiri-force-page-size requires a power of 2: {page_size}");
             };
             miri_config.page_size = Some(page_size);
+        } else if let Some(param) = arg.strip_prefix("-Zmiri-user-relevant-crates=") {
+            miri_config.user_relevant_crates.extend(param.split(',').map(|s| s.to_owned()));
         } else {
             // Forward to rustc.
             rustc_args.push(arg);

src/bin/miri.rs

@@ -675,16 +675,22 @@ trait EvalContextPrivExt<'tcx, 'ecx>: crate::MiriInterpCxExt<'tcx> {
             if let Ok((alloc_id, base_offset, orig_tag)) = this.ptr_try_get_alloc_id(place.ptr(), 0)
             {
                 log_creation(this, Some((alloc_id, base_offset, orig_tag)))?;
-                // Still give it the new provenance, it got retagged after all.
+                // Still give it the new provenance, it got retagged after all. If this was a
+                // wildcard pointer, this will fix the AllocId and make future accesses with this
+                // reference to other allocations UB, but that's fine: due to subobject provenance,
+                // *all* future accesses with this reference should be UB!
                 return interp_ok(Some(Provenance::Concrete { alloc_id, tag: new_tag }));
             } else {
                 // This pointer doesn't come with an AllocId. :shrug:
                 log_creation(this, None)?;
-                // Provenance unchanged.
+                // Provenance unchanged. Ideally we'd make this pointer UB to use like above,
+                // but there's no easy way to do that.
                 return interp_ok(place.ptr().provenance);
             }
         }
 
+        // The pointer *must* have a valid AllocId to continue, so we want to resolve this to
+        // a concrete ID even for wildcard pointers.
         let (alloc_id, base_offset, orig_tag) = this.ptr_get_alloc_id(place.ptr(), 0)?;
         log_creation(this, Some((alloc_id, base_offset, orig_tag)))?;
 
@@ -743,7 +749,7 @@ trait EvalContextPrivExt<'tcx, 'ecx>: crate::MiriInterpCxExt<'tcx> {
                     // Make sure the data race model also knows about this.
                     // FIXME(genmc): Ensure this is still done in GenMC mode. Check for other places where GenMC may need to be informed.
                     if let Some(data_race) = alloc_extra.data_race.as_vclocks_mut() {
-                        data_race.write(
+                        data_race.write_non_atomic(
                             alloc_id,
                             range,
                             NaWriteType::Retag,
@@ -792,7 +798,7 @@ trait EvalContextPrivExt<'tcx, 'ecx>: crate::MiriInterpCxExt<'tcx> {
                         assert_eq!(access, AccessKind::Read);
                         // Make sure the data race model also knows about this.
                         if let Some(data_race) = alloc_extra.data_race.as_vclocks_ref() {
-                            data_race.read(
+                            data_race.read_non_atomic(
                                 alloc_id,
                                 range,
                                 NaReadType::Retag,