Update docs for unsafe_op_in_unsafe_fn stability.

[ehuss]

The unsafe_op_in_unsafe_fn lint was stabilized in #79208, but the bottom of this documentation wasn't updated.

I'm just guessing at the reason here, hopefully it is close to correct. The only discussion I found is #71668 (comment) which didn't really explain the thought process behind the decision.

[rust-highfive]

r? @varkor

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[jyn514]

r? @LeSeulArtichaut

[LeSeulArtichaut]

Looks good to me. I don't have r+ priviledges though, maybe r? @RalfJung

[RalfJung]

LGTM, thanks!
@bors r+ rollup

[bors]

📌 Commit e67f443 has been approved by RalfJung

[bors]

⌛ Testing commit e67f443 with merge b5eafa531c034d9908409e65e0977494c06d9dd1...

[rust-log-analyzer]

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

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

      Memory: 14 GB
      Boot ROM Version: VMW71.00V.13989454.B64.1906190538
      Apple ROM Info: [MS_VM_CERT/SHA1/27d66596a61c48dd3dc7216fd715126e33f59ae7]Welcome to the Virtual Machine
      SMC Version (system): 2.8f0
      Serial Number (system): VMWp6BFvq3Ow

hw.ncpu: 3
hw.byteorder: 1234
hw.memsize: 15032385536
---
failures:

---- [ui] ui/abi/abi-sysv64-arg-passing.rs stdout ----

error: test compilation failed although it shouldn't!
status: signal: 9
command: "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/stage2/bin/rustc" "/Users/runner/work/rust/rust/src/test/ui/abi/abi-sysv64-arg-passing.rs" "-Zthreads=1" "--target=x86_64-apple-darwin" "--error-format" "json" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zemit-future-incompat-report" "-C" "prefer-dynamic" "-o" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/ui/abi/abi-sysv64-arg-passing/a" "-Crpath" "-O" "-Cdebuginfo=0" "-Zunstable-options" "-Lnative=/Users/runner/work/rust/rust/build/x86_64-apple-darwin/native/rust-test-helpers" "-L" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/ui/abi/abi-sysv64-arg-passing/auxiliary"
------------------------------------------

------------------------------------------
stderr:
---

Some tests failed in compiletest suite=ui mode=ui host=x86_64-apple-darwin target=x86_64-apple-darwin


command did not execute successfully: "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/stage0-tools-bin/compiletest" "--compile-lib-path" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/stage2/lib" "--run-lib-path" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/stage2/lib/rustlib/x86_64-apple-darwin/lib" "--rustc-path" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/stage2/bin/rustc" "--src-base" "/Users/runner/work/rust/rust/src/test/ui" "--build-base" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/ui" "--stage-id" "stage2-x86_64-apple-darwin" "--suite" "ui" "--mode" "ui" "--target" "x86_64-apple-darwin" "--host" "x86_64-apple-darwin" "--llvm-filecheck" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/llvm/build/bin/FileCheck" "--nodejs" "/usr/local/bin/node" "--npm" "/usr/local/bin/npm" "--host-rustcflags" "-Crpath -O -Cdebuginfo=0 -Zunstable-options  -Lnative=/Users/runner/work/rust/rust/build/x86_64-apple-darwin/native/rust-test-helpers" "--target-rustcflags" "-Crpath -O -Cdebuginfo=0 -Zunstable-options  -Lnative=/Users/runner/work/rust/rust/build/x86_64-apple-darwin/native/rust-test-helpers" "--docck-python" "/usr/local/opt/python@3.9/bin/python3.9" "--lldb-python" "/usr/bin/python3" "--lldb-version" "lldb-1200.0.44.2\nApple Swift version 5.3.2 (swiftlang-1200.0.45 clang-1200.0.32.28)\n" "--lldb-python-dir" "/Applications/Xcode_12.4.app/Contents/SharedFrameworks/LLDB.framework/Resources/Python3" "--llvm-version" "12.0.0-rust-1.53.0-nightly" "--llvm-components" "aarch64 aarch64asmparser aarch64codegen aarch64desc aarch64disassembler aarch64info aarch64utils aggressiveinstcombine all all-targets analysis arm armasmparser armcodegen armdesc armdisassembler arminfo armutils asmparser asmprinter avr avrasmparser avrcodegen avrdesc avrdisassembler avrinfo binaryformat bitreader bitstreamreader bitwriter cfguard codegen core coroutines coverage debuginfocodeview debuginfodwarf debuginfogsym debuginfomsf debuginfopdb demangle dlltooldriver dwarflinker engine executionengine extensions filecheck frontendopenacc frontendopenmp fuzzmutate globalisel hellonew hexagon hexagonasmparser hexagoncodegen hexagondesc hexagondisassembler hexagoninfo instcombine instrumentation interfacestub interpreter ipo irreader jitlink libdriver lineeditor linker lto mc mca mcdisassembler mcjit mcparser mips mipsasmparser mipscodegen mipsdesc mipsdisassembler mipsinfo mirparser msp430 msp430asmparser msp430codegen msp430desc msp430disassembler msp430info native nativecodegen nvptx nvptxcodegen nvptxdesc nvptxinfo objcarcopts object objectyaml option orcjit orcshared orctargetprocess passes powerpc powerpcasmparser powerpccodegen powerpcdesc powerpcdisassembler powerpcinfo profiledata remarks riscv riscvasmparser riscvcodegen riscvdesc riscvdisassembler riscvinfo runtimedyld scalaropts selectiondag sparc sparcasmparser sparccodegen sparcdesc sparcdisassembler sparcinfo support symbolize systemz systemzasmparser systemzcodegen systemzdesc systemzdisassembler systemzinfo tablegen target textapi transformutils vectorize webassembly webassemblyasmparser webassemblycodegen webassemblydesc webassemblydisassembler webassemblyinfo windowsmanifest x86 x86asmparser x86codegen x86desc x86disassembler x86info xray" "--cc" "" "--cxx" "" "--cflags" "" "--adb-path" "adb" "--adb-test-dir" "/data/tmp/work" "--android-cross-path" "" "--color" "always"


failed to run: /Users/runner/work/rust/rust/build/bootstrap/debug/bootstrap --stage 2 test
Build completed unsuccessfully in 1:21:51

[bors]

💔 Test failed - checks-actions

[ehuss]

@bors retry

ui/abi/abi-sysv64-arg-passing.rs failed with signal 9 on x86_64-apple. Have not seen that before.

[bors]

⌛ Testing commit e67f443 with merge 0894d1e...

[bors]

☀️ Test successful - checks-actions
Approved by: RalfJung
Pushing 0894d1e to master...