user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Merge pull request #4437 from RalfJung/env-cleanup

Browse source 
skip env var memory for leak check
This commit is contained in:
Ralf Jung 2025-07-02 10:40:11 +00:00 • committed by GitHub
commit 5ce7a04910
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
5 changed files with 9 additions and 50 deletions
Download patch file Download diff file Expand all files Collapse all files

8
src/tools/miri/src/concurrency/data_race.rs
View file

@ -971,14 +971,6 @@ pub trait EvalContextExt<'tcx>: MiriInterpCxExt<'tcx> {
}
}
/// After all threads are done running, this allows data races to occur for subsequent
/// 'administrative' machine accesses (that logically happen outside of the Abstract Machine).
fn allow_data_races_all_threads_done(&mut self) {
let this = self.eval_context_ref();
assert!(this.have_all_terminated());
this.machine.data_race.set_ongoing_action_data_race_free(true);
}
/// Calls the callback with the "release" clock of the current thread.
/// Other threads can acquire this clock in the future to establish synchronization
/// with this program point.

10
src/tools/miri/src/eval.rs
View file

@ -283,16 +283,6 @@ impl<'tcx> MainThreadState<'tcx> {
// to be like a global `static`, so that all memory reached by it is considered to "not leak".
this.terminate_active_thread(TlsAllocAction::Leak)?;
// Machine cleanup. Only do this if all threads have terminated; threads that are still running
// might cause Stacked Borrows errors (https://github.com/rust-lang/miri/issues/2396).
if this.have_all_terminated() {
// Even if all threads have terminated, we have to beware of data races since some threads
// might not have joined the main thread (https://github.com/rust-lang/miri/issues/2020,
// https://github.com/rust-lang/miri/issues/2508).
this.allow_data_races_all_threads_done();
EnvVars::cleanup(this).expect("error during env var cleanup");
}
// Stop interpreter loop.
throw_machine_stop!(TerminationInfo::Exit { code: exit_code, leak_check: true });
}

6
src/tools/miri/src/machine.rs
View file

@ -130,11 +130,11 @@ pub enum MiriMemoryKind {
WinHeap,
/// Windows "local" memory (to be freed with `LocalFree`)
WinLocal,
/// Memory for args, errno, and other parts of the machine-managed environment.
/// Memory for args, errno, env vars, and other parts of the machine-managed environment.
/// This memory may leak.
Machine,
/// Memory allocated by the runtime (e.g. env vars). Separate from `Machine`
/// because we clean it up and leak-check it.
/// Memory allocated by the runtime, e.g. for readdir. Separate from `Machine` because we clean
/// it up (or expect the user to invoke operations that clean it up) and leak-check it.
Runtime,
/// Globals copied from `tcx`.
/// This memory may leak.

9
src/tools/miri/src/shims/env.rs
View file

@ -59,15 +59,6 @@ impl<'tcx> EnvVars<'tcx> {
interp_ok(())
}
pub(crate) fn cleanup(ecx: &mut InterpCx<'tcx, MiriMachine<'tcx>>) -> InterpResult<'tcx> {
let this = ecx.eval_context_mut();
match this.machine.env_vars {
EnvVars::Unix(_) => UnixEnvVars::cleanup(this),
EnvVars::Windows(_) => interp_ok(()), // no cleanup needed
EnvVars::Uninit => interp_ok(()),
}
}
pub(crate) fn unix(&self) -> &UnixEnvVars<'tcx> {
match self {
EnvVars::Unix(env) => env,

26
src/tools/miri/src/shims/unix/env.rs
View file

@ -1,6 +1,6 @@
use std::env;
use std::ffi::{OsStr, OsString};
use std::io::ErrorKind;
use std::{env, mem};
use rustc_abi::{FieldIdx, Size};
use rustc_data_structures::fx::FxHashMap;
@ -50,20 +50,6 @@ impl<'tcx> UnixEnvVars<'tcx> {
interp_ok(UnixEnvVars { map: env_vars_machine, environ })
}
pub(crate) fn cleanup(ecx: &mut InterpCx<'tcx, MiriMachine<'tcx>>) -> InterpResult<'tcx> {
// Deallocate individual env vars.
let env_vars = mem::take(&mut ecx.machine.env_vars.unix_mut().map);
for (_name, ptr) in env_vars {
ecx.deallocate_ptr(ptr, None, MiriMemoryKind::Runtime.into())?;
}
// Deallocate environ var list.
let environ = &ecx.machine.env_vars.unix().environ;
let old_vars_ptr = ecx.read_pointer(environ)?;
ecx.deallocate_ptr(old_vars_ptr, None, MiriMemoryKind::Runtime.into())?;
interp_ok(())
}
pub(crate) fn environ(&self) -> Pointer {
self.environ.ptr()
}
@ -112,7 +98,7 @@ fn alloc_env_var<'tcx>(
let mut name_osstring = name.to_os_string();
name_osstring.push("=");
name_osstring.push(value);
ecx.alloc_os_str_as_c_str(name_osstring.as_os_str(), MiriMemoryKind::Runtime.into())
ecx.alloc_os_str_as_c_str(name_osstring.as_os_str(), MiriMemoryKind::Machine.into())
}
/// Allocates an `environ` block with the given list of pointers.
@ -128,7 +114,7 @@ fn alloc_environ_block<'tcx>(
ecx.machine.layouts.mut_raw_ptr.ty,
u64::try_from(vars.len()).unwrap(),
))?;
let vars_place = ecx.allocate(vars_layout, MiriMemoryKind::Runtime.into())?;
let vars_place = ecx.allocate(vars_layout, MiriMemoryKind::Machine.into())?;
for (idx, var) in vars.into_iter_enumerated() {
let place = ecx.project_field(&vars_place, idx)?;
ecx.write_pointer(var, &place)?;
@ -171,7 +157,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
if let Some((name, value)) = new {
let var_ptr = alloc_env_var(this, &name, &value)?;
if let Some(var) = this.machine.env_vars.unix_mut().map.insert(name, var_ptr) {
this.deallocate_ptr(var, None, MiriMemoryKind::Runtime.into())?;
this.deallocate_ptr(var, None, MiriMemoryKind::Machine.into())?;
}
this.update_environ()?;
interp_ok(Scalar::from_i32(0)) // return zero on success
@ -195,7 +181,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
}
if let Some(old) = success {
if let Some(var) = old {
this.deallocate_ptr(var, None, MiriMemoryKind::Runtime.into())?;
this.deallocate_ptr(var, None, MiriMemoryKind::Machine.into())?;
}
this.update_environ()?;
interp_ok(Scalar::from_i32(0))
@ -253,7 +239,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
// Deallocate the old environ list.
let environ = this.machine.env_vars.unix().environ.clone();
let old_vars_ptr = this.read_pointer(&environ)?;
this.deallocate_ptr(old_vars_ptr, None, MiriMemoryKind::Runtime.into())?;
this.deallocate_ptr(old_vars_ptr, None, MiriMemoryKind::Machine.into())?;
// Write the new list.
let vals = this.machine.env_vars.unix().map.values().copied().collect();