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Merged
merged 1 commit into from
Jul 15, 2025

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oli-obk
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@oli-obk oli-obk commented Jul 10, 2025

This makes all bytes of TypeId uninspectable at compile-time.

For context see #77125 (comment)

r? @RalfJung

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rustbot commented Jul 10, 2025

Some changes occurred to the CTFE machinery

cc @RalfJung, @oli-obk, @lcnr

Some changes occurred to the CTFE / Miri interpreter

cc @rust-lang/miri

@rustbot rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Jul 10, 2025
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LGTM, r=me with comment nits resolved. :)

Comment on lines 54 to 55
let offset = self.read_scalar(&elem)?.to_target_usize(&tcx)?;
let ptr = Pointer::new(alloc_id.into(), Size::from_bytes(offset));
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Suggested change
let offset = self.read_scalar(&elem)?.to_target_usize(&tcx)?;
let ptr = Pointer::new(alloc_id.into(), Size::from_bytes(offset));
// Decorate this part of the hash with provenance; leave the integer part unchanged.
let hash_fragment = self.read_scalar(&elem)?.to_target_usize(&tcx)?;
let ptr = Pointer::new(alloc_id.into(), Size::from_bytes(hash_fragment));

let mut b = TypeId::of::<()>();
unsafe {
let ptr = &mut b as *mut TypeId as *mut *const ();
let val = std::ptr::read(ptr);
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Suggested change
let val = std::ptr::read(ptr);
// Copy the ptr at index 0 to index 1.
let val = std::ptr::read(ptr);

@oli-obk oli-obk force-pushed the uninspectable-type-id branch from 2f16de4 to aa4675c Compare July 14, 2025 08:27
@oli-obk oli-obk force-pushed the uninspectable-type-id branch from aa4675c to eef08a3 Compare July 14, 2025 08:33
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oli-obk commented Jul 14, 2025

@bors r=RalfJung

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bors commented Jul 14, 2025

📌 Commit eef08a3 has been approved by RalfJung

It is now in the queue for this repository.

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jul 14, 2025
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oli-obk commented Jul 15, 2025

@bors rollup

bors added a commit that referenced this pull request Jul 15, 2025
Rollup of 13 pull requests

Successful merges:

 - #142301 (tests: Fix duplicated-path-in-error fail with musl)
 - #143630 (Drop `./x suggest`)
 - #143736 (Give all bytes of TypeId provenance)
 - #143752 (Don't panic if WASI_SDK_PATH not set when detecting compiler)
 - #143837 (Adjust `run_make_support::symbols` helpers)
 - #143878 (Port `#[pointee]` to the new attribute parsing infrastructure)
 - #143905 (Recover and suggest to use `;` to construct array type)
 - #143907 (core: make `str::split_at_unchecked()` inline)
 - #143910 (Add experimental `backtrace-trace-only` std feature)
 - #143927 (Preserve constness in trait objects up to hir ty lowering)
 - #143935 (rustc_type_ir/walk: move docstring to `TypeWalker` itself)
 - #143938 (Update books)
 - #143941 (update `cfg_select!` documentation)

Failed merges:

 - #143926 (Remove deprecated fields in bootstrap)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit e66f26f into rust-lang:master Jul 15, 2025
11 checks passed
@rustbot rustbot added this to the 1.90.0 milestone Jul 15, 2025
rust-timer added a commit that referenced this pull request Jul 15, 2025
Rollup merge of #143736 - oli-obk:uninspectable-type-id, r=RalfJung

Give all bytes of TypeId provenance

This makes all bytes of TypeId uninspectable at compile-time.

For context see #77125 (comment)

r? ``@RalfJung``
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4 participants