Auto merge of #53832 - pietroalbini:rollup, r=pietroalbini

Rollup of 20 pull requests

Successful merges:

 - #51760 (Add another PartialEq example)
 - #53113 (Add example for Cow)
 - #53129 (remove `let x = baz` which was obscuring the real error)
 - #53389 (document effect of join on memory ordering)
 - #53472 (Use FxHash{Map,Set} instead of the default Hash{Map,Set} everywhere in rustc.)
 - #53476 (Add partialeq implementation for TryFromIntError type)
 - #53513 (Force-inline `shallow_resolve` at its hottest call site.)
 - #53655 (set applicability)
 - #53702 (Fix stabilisation version for macro_vis_matcher.)
 - #53727 (Do not suggest dereferencing in macro)
 - #53732 (save-analysis: Differentiate foreign functions and statics.)
 - #53740 (add llvm-readobj to llvm-tools-preview)
 - #53743 (fix a typo: taget_env -> target_env)
 - #53747 (Rustdoc fixes)
 - #53753 (expand keep-stage --help text)
 - #53756 (Fix typo in comment)
 - #53768 (move file-extension based .gitignore down to src/)
 - #53785 (Fix a comment in src/libcore/slice/mod.rs)
 - #53786 (Replace usages of 'bad_style' with 'nonstandard_style'.)
 - #53806 (Fix UI issues on Implementations on Foreign types)

Failed merges:

r? @ghost

Author: bors

.gitignore

@@ -1,49 +1,3 @@
-*.a
-*.aux
-*.bc
-*.boot
-*.bz2
-*.cmi
-*.cmo
-*.cmx
-*.cp
-*.cps
-*.d
-*.dSYM
-*.def
-*.diff
-*.dll
-*.dylib
-*.elc
-*.epub
-*.exe
-*.fn
-*.html
-*.kdev4
-*.ky
-*.ll
-*.llvm
-*.log
-*.o
-*.orig
-*.out
-*.patch
-*.pdb
-*.pdf
-*.pg
-*.pot
-*.pyc
-*.rej
-*.rlib
-*.rustc
-*.so
-*.swo
-*.swp
-*.tmp
-*.toc
-*.tp
-*.vr
-*.x86
 *~
 .#*
 .DS_Store

src/.gitignore

@@ -0,0 +1,46 @@
+*.a
+*.aux
+*.bc
+*.boot
+*.bz2
+*.cmi
+*.cmo
+*.cmx
+*.cp
+*.cps
+*.d
+*.dSYM
+*.def
+*.diff
+*.dll
+*.dylib
+*.elc
+*.epub
+*.exe
+*.fn
+*.html
+*.kdev4
+*.ky
+*.ll
+*.llvm
+*.log
+*.o
+*.orig
+*.out
+*.patch
+*.pdb
+*.pdf
+*.pg
+*.pot
+*.pyc
+*.rej
+*.rlib
+*.rustc
+*.so
+*.swo
+*.swp
+*.tmp
+*.toc
+*.tp
+*.vr
+*.x86