fix: correct typos and improve comments in compiler code

[RubinovaAn1097]

• Replaced “unstalled” with “uninstalled” and “thie” → “this” in comments.
• Fixed “replacable” to “replaceable.”
• Tweaked wording in a few spots for clarity.
• No logic changes—just doc/comment updates.

[rustbot]

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[rustbot]

The Miri subtree was changed

cc @rust-lang/miri

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[rust-log-analyzer]

The job x86_64-gnu-llvm-18 failed! Check out the build log: (web) (plain)

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

#21 exporting to docker image format
#21 sending tarball 28.9s done
#21 DONE 31.7s
##[endgroup]
Setting extra environment values for docker:  --env ENABLE_GCC_CODEGEN=1 --env GCC_EXEC_PREFIX=/usr/lib/gcc/
[CI_JOB_NAME=x86_64-gnu-llvm-18]
debug: `DISABLE_CI_RUSTC_IF_INCOMPATIBLE` configured.
---
sccache: Starting the server...
##[group]Configure the build
configure: processing command line
configure: 
configure: build.configure-args := ['--build=x86_64-unknown-linux-gnu', '--llvm-root=/usr/lib/llvm-18', '--enable-llvm-link-shared', '--set', 'rust.randomize-layout=true', '--set', 'rust.thin-lto-import-instr-limit=10', '--enable-verbose-configure', '--enable-sccache', '--disable-manage-submodules', '--enable-locked-deps', '--enable-cargo-native-static', '--set', 'rust.codegen-units-std=1', '--set', 'dist.compression-profile=balanced', '--dist-compression-formats=xz', '--set', 'rust.lld=false', '--disable-dist-src', '--release-channel=nightly', '--enable-debug-assertions', '--enable-overflow-checks', '--enable-llvm-assertions', '--set', 'rust.verify-llvm-ir', '--set', 'rust.codegen-backends=llvm,cranelift,gcc', '--set', 'llvm.static-libstdcpp', '--enable-new-symbol-mangling']
configure: target.x86_64-unknown-linux-gnu.llvm-config := /usr/lib/llvm-18/bin/llvm-config
configure: llvm.link-shared     := True
configure: rust.randomize-layout := True
configure: rust.thin-lto-import-instr-limit := 10
---
   Compiling rustc_mir_build v0.0.0 (/checkout/compiler/rustc_mir_build)
   Compiling rustc_codegen_llvm v0.0.0 (/checkout/compiler/rustc_codegen_llvm)
   Compiling rustc_passes v0.0.0 (/checkout/compiler/rustc_passes)
   Compiling rustc_hir_typeck v0.0.0 (/checkout/compiler/rustc_hir_typeck)
error[E0599]: no method named `drain_uninstalled_obligations` found for struct `RefMut<'_, Box<dyn TraitEngine<'tcx, FulfillmentError<'tcx>>>>` in the current scope
   --> compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs:653:58
    |
653 |                 .extend(self.fulfillment_cx.borrow_mut().drain_uninstalled_obligations(&self.infcx));
    |
    = note: the full type name has been written to '/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps/rustc_hir_typeck-497c32004ef9a228.long-type-18292553422879761999.txt'
    = note: consider using `--verbose` to print the full type name to the console
help: there is a method `drain_unstalled_obligations` with a similar name
help: there is a method `drain_unstalled_obligations` with a similar name
    |
653 |                 .extend(self.fulfillment_cx.borrow_mut().drain_unstalled_obligations(&self.infcx));

   Compiling rustc_mir_transform v0.0.0 (/checkout/compiler/rustc_mir_transform)
For more information about this error, try `rustc --explain E0599`.
error: could not compile `rustc_hir_typeck` (lib) due to 1 previous error

[saethlin]

We have gotten a number of typo-fixing PRs recently that look like either identify farming or seeking of extrinsic rewards. This looks like one of those, especially because it doesn't compile, and one of the changes is wrong.

[RalfJung]

In particular, "unstalled" is an actual word, meaning "not stalled" or "no longer stalled".

[workingjubilee]

hello! sorry for any confusion, but we actually are treating it on the merit.

we have plenty of typos in our user-facing documentation for which we are always happy to accept PRs for, but typo fixes that are confined to a random smattering of internal compiler comments are not useful. they are in fact churn that outweighs the benefit.