remove remaining rustc_allowed_through_unstable_modules

[RalfJung]

Let's see if we can actually fully undo this accidental stabilization. Would be nice to be able to get rid of this hack in the compiler.

[RalfJung]

@bors try

[rust-log-analyzer]

The job aarch64-gnu-llvm-21-1 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

Saved the actual stderr to `/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/stability-attribute/accidental-stable-in-unstable/accidental-stable-in-unstable.stderr`
diff of stderr:

7    = help: add `#![feature(unicode_internals)]` to the crate attributes to enable
8    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
9 
- warning: use of deprecated module `std::intrinsics`: import this function via `std::mem` instead
-   --> $DIR/accidental-stable-in-unstable.rs:10:23
+ error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
+   --> $DIR/accidental-stable-in-unstable.rs:10:5
12    |
13 LL | use core::intrinsics::transmute; // depended upon by rand_core
-    |                       ^^^^^^^^^
+    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
15    |
-    = note: `#[warn(deprecated)]` on by default
+    = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
+    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
17 
- error: aborting due to 1 previous error; 1 warning emitted
+ error: aborting due to 2 previous errors
19 
20 For more information about this error, try `rustc --explain E0658`.
21 

Note: some mismatched output was normalized before being compared
-   --> /checkout/tests/ui/stability-attribute/accidental-stable-in-unstable.rs:10:5
+ error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
+   --> $DIR/accidental-stable-in-unstable.rs:10:5
+    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+    = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
+    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
+ error: aborting due to 2 previous errors


The actual stderr differed from the expected stderr
To update references, rerun the tests and pass the `--bless` flag
To only update this specific test, also pass `--test-args stability-attribute/accidental-stable-in-unstable.rs`

error: 1 errors occurred comparing output.
status: exit status: 1
command: env -u RUSTC_LOG_COLOR RUSTC_ICE="0" RUST_BACKTRACE="short" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/tests/ui/stability-attribute/accidental-stable-in-unstable.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/cargo" "-Z" "ignore-directory-in-diagnostics-source-blocks=/checkout/vendor" "--sysroot" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2" "--target=aarch64-unknown-linux-gnu" "--check-cfg" "cfg(test,FALSE)" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/stability-attribute/accidental-stable-in-unstable" "-A" "unused" "-W" "unused_attributes" "-A" "internal_features" "-A" "incomplete_features" "-A" "unused_parens" "-A" "unused_braces" "-Crpath" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/aarch64-unknown-linux-gnu/native/rust-test-helpers"
stdout: none
--- stderr -------------------------------
error[E0658]: use of unstable library feature `unicode_internals`
##[error]  --> /checkout/tests/ui/stability-attribute/accidental-stable-in-unstable.rs:6:5
   |
LL | use core::unicode::UNICODE_VERSION; //~ ERROR use of unstable library feature `unicode_internals`
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: add `#![feature(unicode_internals)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
##[error]  --> /checkout/tests/ui/stability-attribute/accidental-stable-in-unstable.rs:10:5
   |
LL | use core::intrinsics::transmute; // depended upon by rand_core
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0658`.
------------------------------------------

---- [ui] tests/ui/stability-attribute/accidental-stable-in-unstable.rs stdout end ----
---- [ui] tests/ui/stability-attribute/issue-99286-stable-intrinsics.rs stdout ----

error: test compilation failed although it shouldn't!
status: exit status: 1
command: env -u RUSTC_LOG_COLOR RUSTC_ICE="0" RUST_BACKTRACE="short" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/tests/ui/stability-attribute/issue-99286-stable-intrinsics.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/cargo" "-Z" "ignore-directory-in-diagnostics-source-blocks=/checkout/vendor" "--sysroot" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2" "--target=aarch64-unknown-linux-gnu" "--check-cfg" "cfg(test,FALSE)" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/stability-attribute/issue-99286-stable-intrinsics" "-A" "unused" "-W" "unused_attributes" "-A" "internal_features" "-A" "incomplete_features" "-A" "unused_parens" "-A" "unused_braces" "-Crpath" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/aarch64-unknown-linux-gnu/native/rust-test-helpers"
stdout: none
--- stderr -------------------------------
error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
##[error]  --> /checkout/tests/ui/stability-attribute/issue-99286-stable-intrinsics.rs:11:5
   |
LL | use std::intrinsics::copy_nonoverlapping as _;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
##[error]  --> /checkout/tests/ui/stability-attribute/issue-99286-stable-intrinsics.rs:12:5
   |
LL | use std::intrinsics::copy as _;
   |     ^^^^^^^^^^^^^^^^^^^^^
   |
   = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
##[error]  --> /checkout/tests/ui/stability-attribute/issue-99286-stable-intrinsics.rs:13:5
   |
LL | use std::intrinsics::write_bytes as _;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
##[error]  --> /checkout/tests/ui/stability-attribute/issue-99286-stable-intrinsics.rs:14:23
   |
LL | use std::intrinsics::{copy_nonoverlapping, copy, write_bytes};
   |                       ^^^^^^^^^^^^^^^^^^^
   |
   = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
##[error]  --> /checkout/tests/ui/stability-attribute/issue-99286-stable-intrinsics.rs:14:44
   |
LL | use std::intrinsics::{copy_nonoverlapping, copy, write_bytes};
   |                                            ^^^^
   |
   = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error[E0658]: use of unstable library feature `core_intrinsics`: intrinsics are unlikely to ever be stabilized, instead they should be used through stabilized interfaces in the rest of the standard library
##[error]  --> /checkout/tests/ui/stability-attribute/issue-99286-stable-intrinsics.rs:14:50
   |
LL | use std::intrinsics::{copy_nonoverlapping, copy, write_bytes};
   |                                                  ^^^^^^^^^^^
   |
   = help: add `#![feature(core_intrinsics)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date

error: aborting due to 6 previous errors

For more information about this error, try `rustc --explain E0658`.
------------------------------------------

[rust-bors]

☀️ Try build successful (CI)
Build commit: 901d6c1 (901d6c1c62d7c61e05469e996c297476078ee06b, parent: cced03bfd61a304243a34504618ecec86c17063f)

[RalfJung]

@craterbot check

[craterbot]

👌 Experiment pr-157082 created and queued.
🤖 Automatically detected try build 901d6c1
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[theemathas]

@craterbot cancel

See #157814

[craterbot]

🗑️ Experiment pr-157082 deleted!

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[theemathas]

@craterbot check p=1 crates=https://crater-reports.s3.amazonaws.com/pr-157814-crater-rollup/retry-regressed-list.txt

[craterbot]

👌 Experiment pr-157082 created and queued.
🤖 Automatically detected try build 901d6c1
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[craterbot]

🚧 Experiment pr-157082 is now running

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[craterbot]

🎉 Experiment pr-157082 is completed!
📊 7859 regressed and 0 fixed (14695 total)
📊 588 spurious results on the retry-regressed-list.txt, consider a retry¹ if this is a significant amount.
📰 Open the summary report.

⚠️ If you notice any spurious failure please add them to the denylist!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

Footnotes

1. re-run the experiment with crates=https://crater-reports.s3.amazonaws.com/pr-157082/retry-regressed-list.txt ↩

[RalfJung]

Older versions of rand had a use core::intrinsics::transmute;...
There's also trim-in-place, which seems unmaintained, and old versions of wide.

So yeah we won't be able to remove these any time soon. We could possibly remove just some of them but that doesn't seem worth it.