Auto merge of #90598 - JohnTitor:rollup-kz1qioz, r=JohnTitor

Rollup of 9 pull requests

Successful merges:

 - #90507 (Suggest `extern crate alloc` when using undeclared module `alloc`)
 - #90530 (Simplify js tester a bit)
 - #90533 (Add note about x86 instruction prefixes in asm! to unstable book)
 - #90537 (Update aarch64 `target_feature` list for LLVM 12.)
 - #90544 (Demote metadata load warning to "info".)
 - #90554 (Clean up some `-Z unstable-options` in tests.)
 - #90556 (Add more text and examples to `carrying_{add|mul}`)
 - #90563 (rustbot allow labels)
 - #90571 (Fix missing bottom border for headings in sidebar)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

30 files changed, 74 insertions, 62 deletions

diff --git a/src/doc/unstable-book/src/library-features/asm.md b/src/doc/unstable-book/src/library-features/asm.md
index 6bf21e8f58b..84fc6dcc339 100644
--- a/src/doc/unstable-book/src/library-features/asm.md
+++ b/src/doc/unstable-book/src/library-features/asm.md
@@ -885,5 +885,7 @@ The compiler performs some additional checks on options:
     - You are responsible for switching any target-specific state (e.g. thread-local storage, stack bounds).
     - The set of memory locations that you may access is the intersection of those allowed by the `asm!` blocks you entered and exited.
 - You cannot assume that an `asm!` block will appear exactly once in the output binary. The compiler is allowed to instantiate multiple copies of the `asm!` block, for example when the function containing it is inlined in multiple places.
+- On x86, inline assembly must not end with an instruction prefix (such as `LOCK`) that would apply to instructions generated by the compiler.
+  - The compiler is currently unable to detect this due to the way inline assembly is compiled, but may catch and reject this in the future.
 
 > **Note**: As a general rule, the flags covered by `preserves_flags` are those which are *not* preserved when performing a function call.
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index 93cbc0debb9..89a763ef6d7 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -156,7 +156,8 @@ h1.fqn > .in-band > a:hover {
 	section hierarchies. */
 h2,
 .top-doc h3,
-.top-doc h4 {
+.top-doc h4,
+.sidebar .others h3 {
 	border-bottom: 1px solid;
 }
 h3.code-header {
diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index c421c6e9dc1..4b55a0a69b6 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -566,6 +566,7 @@ function hideThemeButtonState() {
     // delayed sidebar rendering.
     window.initSidebarItems = function(items) {
         var sidebar = document.getElementsByClassName("sidebar-elems")[0];
+        var others;
         var current = window.sidebarCurrent;
 
         function addSidebarCrates(crates) {
@@ -594,7 +595,7 @@ function hideThemeButtonState() {
                 li.appendChild(link);
                 ul.appendChild(li);
             }
-            sidebar.appendChild(div);
+            others.appendChild(div);
         }
 
         function block(shortty, longty) {
@@ -635,10 +636,14 @@ function hideThemeButtonState() {
                 ul.appendChild(li);
             }
             div.appendChild(ul);
-            sidebar.appendChild(div);
+            others.appendChild(div);
         }
 
         if (sidebar) {
+            others = document.createElement("div");
+            others.className = "others";
+            sidebar.appendChild(others);
+
             var isModule = hasClass(document.body, "mod");
             if (!isModule) {
                 block("primitive", "Primitive Types");
diff --git a/src/test/rustdoc-gui/headings.goml b/src/test/rustdoc-gui/headings.goml
index 35d772170f6..bdf17ec4570 100644
--- a/src/test/rustdoc-gui/headings.goml
+++ b/src/test/rustdoc-gui/headings.goml
@@ -109,6 +109,9 @@ assert-css: ("h6#sub-heading-for-enum-impl-item-doc", {"border-bottom-width": "0
 assert-css: ("h6#sub-sub-heading-for-enum-impl-item-doc", {"font-size": "15.2px"})
 assert-css: ("h6#sub-sub-heading-for-enum-impl-item-doc", {"border-bottom-width": "0px"})
 
+assert-text: (".sidebar .others h3", "Modules")
+assert-css: (".sidebar .others h3", {"border-bottom-width": "1px"}, ALL)
+
 goto: file://|DOC_PATH|/test_docs/union.HeavilyDocumentedUnion.html
 
 assert-css: ("h1.fqn", {"font-size": "24px"})
diff --git a/src/test/rustdoc-gui/sidebar.goml b/src/test/rustdoc-gui/sidebar.goml
index eacc9f6c15f..f9c707f81e7 100644
--- a/src/test/rustdoc-gui/sidebar.goml
+++ b/src/test/rustdoc-gui/sidebar.goml
@@ -4,17 +4,17 @@ assert-text: (".sidebar > .location", "Crate test_docs")
 assert-count: (".sidebar .location", 1)
 assert-text: (".sidebar-elems > #all-types", "See all test_docs's items")
 // We check that we have the crates list and that the "current" on is "test_docs".
-assert-text: (".sidebar-elems > .crate > ul > li > a.current", "test_docs")
+assert-text: (".sidebar-elems .crate > ul > li > a.current", "test_docs")
 // And we're also supposed to have the list of items in the current module.
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(1)", "Modules")
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(2)", "Macros")
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(3)", "Structs")
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(4)", "Enums")
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(5)", "Traits")
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(6)", "Functions")
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(7)", "Type Definitions")
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(8)", "Unions")
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(9)", "Keywords")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(1)", "Modules")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(2)", "Macros")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(3)", "Structs")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(4)", "Enums")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(5)", "Traits")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(6)", "Functions")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(7)", "Type Definitions")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(8)", "Unions")
+assert-text: (".sidebar-elems .items > ul > li:nth-child(9)", "Keywords")
 assert-text: ("#structs + .item-table .item-left > a", "Foo")
 click: "#structs + .item-table .item-left > a"
 
@@ -24,13 +24,13 @@ assert-count: (".sidebar .location", 2)
 assert-false: ".sidebar-elems > .crate"
 // We now go back to the crate page to click on the "lib2" crate link.
 goto: file://|DOC_PATH|/test_docs/index.html
-click: ".sidebar-elems > .crate > ul > li:first-child > a"
+click: ".sidebar-elems .crate > ul > li:first-child > a"
 
 // PAGE: lib2/index.html
 goto: file://|DOC_PATH|/lib2/index.html
 assert-text: (".sidebar > .location", "Crate lib2")
 // We check that we have the crates list and that the "current" on is now "lib2".
-assert-text: (".sidebar-elems > .crate > ul > li > a.current", "lib2")
+assert-text: (".sidebar-elems .crate > ul > li > a.current", "lib2")
 // We now go to the "foobar" function page.
 assert-text: (".sidebar-elems > .items > ul > li:nth-child(1)", "Modules")
 assert-text: (".sidebar-elems > .items > ul > li:nth-child(2)", "Structs")
@@ -57,6 +57,6 @@ assert-false: ".sidebar-elems > .crate"
 goto: ./sub_module/sub_sub_module/index.html
 assert-text: (".sidebar > .location", "Module sub_sub_module")
 // We check that we don't have the crate list.
-assert-false: ".sidebar-elems > .crate"
-assert-text: (".sidebar-elems > .items > ul > li:nth-child(1)", "Functions")
+assert-false: ".sidebar-elems .crate"
+assert-text: (".sidebar-elems .items > ul > li:nth-child(1)", "Functions")
 assert-text: ("#functions + .item-table .item-left > a", "foo")
diff --git a/src/test/ui/hello2021.rs b/src/test/ui/hello2021.rs
index 738f151b0f6..134d8af5bfb 100644
--- a/src/test/ui/hello2021.rs
+++ b/src/test/ui/hello2021.rs
@@ -1,6 +1,5 @@
 // run-pass
 // edition:2021
-// compile-flags: -Zunstable-options
 
 fn main() {
     println!("hello, 2021");
diff --git a/src/test/ui/iterators/into-iter-on-arrays-2021.rs b/src/test/ui/iterators/into-iter-on-arrays-2021.rs
index ec54ed00517..158317efe47 100644
--- a/src/test/ui/iterators/into-iter-on-arrays-2021.rs
+++ b/src/test/ui/iterators/into-iter-on-arrays-2021.rs
@@ -1,6 +1,5 @@
 // check-pass
 // edition:2021
-// compile-flags: -Zunstable-options
 
 use std::array::IntoIter;
 use std::ops::Deref;
diff --git a/src/test/ui/lint/force-warn/allowed-cli-deny-by-default-lint.rs b/src/test/ui/lint/force-warn/allowed-cli-deny-by-default-lint.rs
index 3fab9148392..3a3d81176d6 100644
--- a/src/test/ui/lint/force-warn/allowed-cli-deny-by-default-lint.rs
+++ b/src/test/ui/lint/force-warn/allowed-cli-deny-by-default-lint.rs
@@ -1,6 +1,6 @@
 // --force-warn $LINT causes $LINT (which is deny-by-default) to warn
 // despite $LINT being allowed on command line
-// compile-flags: -A const_err --force-warn const_err -Zunstable-options
+// compile-flags: -A const_err --force-warn const_err
 // check-pass
 
 const C: i32 = 1 / 0;
diff --git a/src/test/ui/lint/force-warn/lint-group-allowed-cli-warn-by-default-lint.rs b/src/test/ui/lint/force-warn/lint-group-allowed-cli-warn-by-default-lint.rs
index 4eb05b538b0..9736027452a 100644
--- a/src/test/ui/lint/force-warn/lint-group-allowed-cli-warn-by-default-lint.rs
+++ b/src/test/ui/lint/force-warn/lint-group-allowed-cli-warn-by-default-lint.rs
@@ -1,6 +1,6 @@
 // --force-warn $LINT_GROUP causes $LINT (which is warn-by-default) to warn
 // despite $LINT being allowed on command line
-// compile-flags: -A bare-trait-objects --force-warn rust-2018-idioms -Zunstable-options
+// compile-flags: -A bare-trait-objects --force-warn rust-2018-idioms
 // check-pass
 
 pub trait SomeTrait {}
diff --git a/src/test/ui/lint/force-warn/warn-by-default-lint-two-modules.rs b/src/test/ui/lint/force-warn/warn-by-default-lint-two-modules.rs
index d2cb3417be6..267e7b45f0c 100644
--- a/src/test/ui/lint/force-warn/warn-by-default-lint-two-modules.rs
+++ b/src/test/ui/lint/force-warn/warn-by-default-lint-two-modules.rs
@@ -1,6 +1,6 @@
 // --force-warn $LINT causes $LINT (which is warn-by-default) to warn
 // despite being allowed in one submodule (but not the other)
-// compile-flags: --force-warn dead_code -Zunstable-options
+// compile-flags: --force-warn dead_code
 // check-pass
 
 mod one {
diff --git a/src/test/ui/lint/force-warn/warnings-lint-group.rs b/src/test/ui/lint/force-warn/warnings-lint-group.rs
index fa25a1f8a84..d1d4f5602f2 100644
--- a/src/test/ui/lint/force-warn/warnings-lint-group.rs
+++ b/src/test/ui/lint/force-warn/warnings-lint-group.rs
@@ -1,5 +1,5 @@
 // --force-warn warnings is an error
-// compile-flags: --force-warn warnings -Zunstable-options
+// compile-flags: --force-warn warnings
 // error-pattern: `warnings` lint group is not supported
 
 fn main() {}
diff --git a/src/test/ui/lint/force-warn/warnings-lint-group.stderr b/src/test/ui/lint/force-warn/warnings-lint-group.stderr
index 03f5788b527..1faeed33704 100644
--- a/src/test/ui/lint/force-warn/warnings-lint-group.stderr
+++ b/src/test/ui/lint/force-warn/warnings-lint-group.stderr
@@ -2,8 +2,6 @@ error[E0602]: `warnings` lint group is not supported with ´--force-warn´
 
 error[E0602]: `warnings` lint group is not supported with ´--force-warn´
 
-error[E0602]: `warnings` lint group is not supported with ´--force-warn´
-
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0602`.
diff --git a/src/test/ui/lint/unused_parens_json_suggestion.fixed b/src/test/ui/lint/unused_parens_json_suggestion.fixed
index 15ee19755bf..c4004540467 100644
--- a/src/test/ui/lint/unused_parens_json_suggestion.fixed
+++ b/src/test/ui/lint/unused_parens_json_suggestion.fixed
@@ -1,4 +1,4 @@
-// compile-flags: --error-format json -Zunstable-options
+// compile-flags: --error-format json
 // run-rustfix
 
 // The output for humans should just highlight the whole span without showing
diff --git a/src/test/ui/lint/unused_parens_json_suggestion.rs b/src/test/ui/lint/unused_parens_json_suggestion.rs
index d72df21e09a..962c8bdd7d7 100644
--- a/src/test/ui/lint/unused_parens_json_suggestion.rs
+++ b/src/test/ui/lint/unused_parens_json_suggestion.rs
@@ -1,4 +1,4 @@
-// compile-flags: --error-format json -Zunstable-options
+// compile-flags: --error-format json
 // run-rustfix
 
 // The output for humans should just highlight the whole span without showing
diff --git a/src/test/ui/lint/unused_parens_json_suggestion.stderr b/src/test/ui/lint/unused_parens_json_suggestion.stderr
index 498c25d2e1c..169fb824021 100644
--- a/src/test/ui/lint/unused_parens_json_suggestion.stderr
+++ b/src/test/ui/lint/unused_parens_json_suggestion.stderr
@@ -1,4 +1,4 @@
-{"message":"unnecessary parentheses around assigned value","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_json_suggestion.rs","byte_start":596,"byte_end":597,"line_start":16,"line_end":16,"column_start":14,"column_end":15,"is_primary":true,"text":[{"text":"    let _a = (1 / (2 + 3));
+{"message":"unnecessary parentheses around assigned value","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_json_suggestion.rs","byte_start":577,"byte_end":578,"line_start":16,"line_end":16,"column_start":14,"column_end":15,"is_primary":true,"text":[{"text":"    let _a = (1 / (2 + 3));
   --> $DIR/unused_parens_json_suggestion.rs:16:14
    |
 LL |     let _a = (1 / (2 + 3));
diff --git a/src/test/ui/lint/unused_parens_remove_json_suggestion.fixed b/src/test/ui/lint/unused_parens_remove_json_suggestion.fixed
index 1d891d328dd..8a57cd57385 100644
--- a/src/test/ui/lint/unused_parens_remove_json_suggestion.fixed
+++ b/src/test/ui/lint/unused_parens_remove_json_suggestion.fixed
@@ -1,4 +1,4 @@
-// compile-flags: --error-format json -Zunstable-options
+// compile-flags: --error-format json
 // run-rustfix
 
 // The output for humans should just highlight the whole span without showing
diff --git a/src/test/ui/lint/unused_parens_remove_json_suggestion.rs b/src/test/ui/lint/unused_parens_remove_json_suggestion.rs
index 494cd184506..952332d54e9 100644
--- a/src/test/ui/lint/unused_parens_remove_json_suggestion.rs
+++ b/src/test/ui/lint/unused_parens_remove_json_suggestion.rs
@@ -1,4 +1,4 @@
-// compile-flags: --error-format json -Zunstable-options
+// compile-flags: --error-format json
 // run-rustfix
 
 // The output for humans should just highlight the whole span without showing
diff --git a/src/test/ui/lint/unused_parens_remove_json_suggestion.stderr b/src/test/ui/lint/unused_parens_remove_json_suggestion.stderr
index 08291b10fcc..43367aaa911 100644
--- a/src/test/ui/lint/unused_parens_remove_json_suggestion.stderr
+++ b/src/test/ui/lint/unused_parens_remove_json_suggestion.stderr
@@ -1,4 +1,4 @@
-{"message":"unnecessary parentheses around `if` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":500,"byte_end":501,"line_start":17,"line_end":17,"column_start":8,"column_end":9,"is_primary":true,"text":[{"text":"    if (_b) {
+{"message":"unnecessary parentheses around `if` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":481,"byte_end":482,"line_start":17,"line_end":17,"column_start":8,"column_end":9,"is_primary":true,"text":[{"text":"    if (_b) {
   --> $DIR/unused_parens_remove_json_suggestion.rs:17:8
    |
 LL |     if (_b) {
@@ -16,7 +16,7 @@ LL +     if _b {
    | 
 
 "}
-{"message":"unnecessary parentheses around `if` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":631,"byte_end":632,"line_start":28,"line_end":28,"column_start":7,"column_end":8,"is_primary":true,"text":[{"text":"    if(c) {
+{"message":"unnecessary parentheses around `if` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":612,"byte_end":613,"line_start":28,"line_end":28,"column_start":7,"column_end":8,"is_primary":true,"text":[{"text":"    if(c) {
   --> $DIR/unused_parens_remove_json_suggestion.rs:28:7
    |
 LL |     if(c) {
@@ -29,7 +29,7 @@ LL +     if c {
    | 
 
 "}
-{"message":"unnecessary parentheses around `if` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":711,"byte_end":712,"line_start":32,"line_end":32,"column_start":8,"column_end":9,"is_primary":true,"text":[{"text":"    if (c){
+{"message":"unnecessary parentheses around `if` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":692,"byte_end":693,"line_start":32,"line_end":32,"column_start":8,"column_end":9,"is_primary":true,"text":[{"text":"    if (c){
   --> $DIR/unused_parens_remove_json_suggestion.rs:32:8
    |
 LL |     if (c){
@@ -42,7 +42,7 @@ LL +     if c {
    | 
 
 "}
-{"message":"unnecessary parentheses around `while` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":793,"byte_end":794,"line_start":36,"line_end":36,"column_start":11,"column_end":12,"is_primary":true,"text":[{"text":"    while (false && true){","highlight_start":11,"highlight_end":12}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":807,"byte_end":808,"line_start":36,"line_end":36,"column_start":25,"column_end":26,"is_primary":true,"text":[{"text":"    while (false && true){","highlight_start":25,"highlight_end":26}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"remove these parentheses","code":null,"level":"help","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":793,"byte_end":794,"line_start":36,"line_end":36,"column_start":11,"column_end":12,"is_primary":true,"text":[{"text":"    while (false && true){","highlight_start":11,"highlight_end":12}],"label":null,"suggested_replacement":"","suggestion_applicability":"MachineApplicable","expansion":null},{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":807,"byte_end":808,"line_start":36,"line_end":36,"column_start":25,"column_end":26,"is_primary":true,"text":[{"text":"    while (false && true){","highlight_start":25,"highlight_end":26}],"label":null,"suggested_replacement":" ","suggestion_applicability":"MachineApplicable","expansion":null}],"children":[],"rendered":null}],"rendered":"error: unnecessary parentheses around `while` condition
+{"message":"unnecessary parentheses around `while` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":774,"byte_end":775,"line_start":36,"line_end":36,"column_start":11,"column_end":12,"is_primary":true,"text":[{"text":"    while (false && true){","highlight_start":11,"highlight_end":12}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null},{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":788,"byte_end":789,"line_start":36,"line_end":36,"column_start":25,"column_end":26,"is_primary":true,"text":[{"text":"    while (false && true){","highlight_start":25,"highlight_end":26}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"remove these parentheses","code":null,"level":"help","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":774,"byte_end":775,"line_start":36,"line_end":36,"column_start":11,"column_end":12,"is_primary":true,"text":[{"text":"    while (false && true){","highlight_start":11,"highlight_end":12}],"label":null,"suggested_replacement":"","suggestion_applicability":"MachineApplicable","expansion":null},{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":788,"byte_end":789,"line_start":36,"line_end":36,"column_start":25,"column_end":26,"is_primary":true,"text":[{"text":"    while (false && true){","highlight_start":25,"highlight_end":26}],"label":null,"suggested_replacement":" ","suggestion_applicability":"MachineApplicable","expansion":null}],"children":[],"rendered":null}],"rendered":"error: unnecessary parentheses around `while` condition
   --> $DIR/unused_parens_remove_json_suggestion.rs:36:11
    |
 LL |     while (false && true){
@@ -55,7 +55,7 @@ LL +     while false && true {
    | 
 
 "}
-{"message":"unnecessary parentheses around `if` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":821,"byte_end":822,"line_start":37,"line_end":37,"column_start":12,"column_end":13,"is_primary":true,"text":[{"text":"        if (c) {
+{"message":"unnecessary parentheses around `if` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":802,"byte_end":803,"line_start":37,"line_end":37,"column_start":12,"column_end":13,"is_primary":true,"text":[{"text":"        if (c) {
   --> $DIR/unused_parens_remove_json_suggestion.rs:37:12
    |
 LL |         if (c) {
@@ -68,7 +68,7 @@ LL +         if c {
    | 
 
 "}
-{"message":"unnecessary parentheses around `while` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":918,"byte_end":919,"line_start":43,"line_end":43,"column_start":10,"column_end":11,"is_primary":true,"text":[{"text":"    while(true && false) {
+{"message":"unnecessary parentheses around `while` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":899,"byte_end":900,"line_start":43,"line_end":43,"column_start":10,"column_end":11,"is_primary":true,"text":[{"text":"    while(true && false) {
   --> $DIR/unused_parens_remove_json_suggestion.rs:43:10
    |
 LL |     while(true && false) {
@@ -81,7 +81,7 @@ LL +     while true && false {
    | 
 
 "}
-{"message":"unnecessary parentheses around `for` iterator expression","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":987,"byte_end":988,"line_start":44,"line_end":44,"column_start":18,"column_end":19,"is_primary":true,"text":[{"text":"        for _ in (0 .. 3){
+{"message":"unnecessary parentheses around `for` iterator expression","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":968,"byte_end":969,"line_start":44,"line_end":44,"column_start":18,"column_end":19,"is_primary":true,"text":[{"text":"        for _ in (0 .. 3){
   --> $DIR/unused_parens_remove_json_suggestion.rs:44:18
    |
 LL |         for _ in (0 .. 3){
@@ -94,7 +94,7 @@ LL +         for _ in 0 .. 3 {
    | 
 
 "}
-{"message":"unnecessary parentheses around `for` iterator expression","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":1088,"byte_end":1089,"line_start":49,"line_end":49,"column_start":14,"column_end":15,"is_primary":true,"text":[{"text":"    for _ in (0 .. 3) {
+{"message":"unnecessary parentheses around `for` iterator expression","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":1069,"byte_end":1070,"line_start":49,"line_end":49,"column_start":14,"column_end":15,"is_primary":true,"text":[{"text":"    for _ in (0 .. 3) {
   --> $DIR/unused_parens_remove_json_suggestion.rs:49:14
    |
 LL |     for _ in (0 .. 3) {
@@ -107,7 +107,7 @@ LL +     for _ in 0 .. 3 {
    | 
 
 "}
-{"message":"unnecessary parentheses around `while` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":1147,"byte_end":1148,"line_start":50,"line_end":50,"column_start":15,"column_end":16,"is_primary":true,"text":[{"text":"        while (true && false) {
+{"message":"unnecessary parentheses around `while` condition","code":{"code":"unused_parens","explanation":null},"level":"error","spans":[{"file_name":"$DIR/unused_parens_remove_json_suggestion.rs","byte_start":1128,"byte_end":1129,"line_start":50,"line_end":50,"column_start":15,"column_end":16,"is_primary":true,"text":[{"text":"        while (true && false) {
   --> $DIR/unused_parens_remove_json_suggestion.rs:50:15
    |
 LL |         while (true && false) {
diff --git a/src/test/ui/matches2021.rs b/src/test/ui/matches2021.rs
index f5497c1d16d..9143a8cdd59 100644
--- a/src/test/ui/matches2021.rs
+++ b/src/test/ui/matches2021.rs
@@ -1,6 +1,5 @@
 // run-pass
 // edition:2021
-// compile-flags: -Zunstable-options
 
 // regression test for https://github.com/rust-lang/rust/pull/85678
 
diff --git a/src/test/ui/privacy/pub-priv-dep/pub-priv1.rs b/src/test/ui/privacy/pub-priv-dep/pub-priv1.rs
index f926eee9d92..ec8666f93f0 100644
--- a/src/test/ui/privacy/pub-priv-dep/pub-priv1.rs
+++ b/src/test/ui/privacy/pub-priv-dep/pub-priv1.rs
@@ -1,5 +1,6 @@
 // aux-crate:priv:priv_dep=priv_dep.rs
 // aux-build:pub_dep.rs
+// compile-flags: -Zunstable-options
 #![deny(exported_private_dependencies)]
 
 // This crate is a private dependency
diff --git a/src/test/ui/privacy/pub-priv-dep/pub-priv1.stderr b/src/test/ui/privacy/pub-priv-dep/pub-priv1.stderr
index e6b4d33f103..f64b8569015 100644
--- a/src/test/ui/privacy/pub-priv-dep/pub-priv1.stderr
+++ b/src/test/ui/privacy/pub-priv-dep/pub-priv1.stderr
@@ -1,23 +1,23 @@
 error: type `OtherType` from private dependency 'priv_dep' in public interface
-  --> $DIR/pub-priv1.rs:20:5
+  --> $DIR/pub-priv1.rs:21:5
    |
 LL |     pub field: OtherType,
    |     ^^^^^^^^^^^^^^^^^^^^
    |
 note: the lint level is defined here
-  --> $DIR/pub-priv1.rs:3:9
+  --> $DIR/pub-priv1.rs:4:9
    |
 LL | #![deny(exported_private_dependencies)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: type `OtherType` from private dependency 'priv_dep' in public interface
-  --> $DIR/pub-priv1.rs:27:5
+  --> $DIR/pub-priv1.rs:28:5
    |
 LL |     pub fn pub_fn(param: OtherType) {}
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: trait `OtherTrait` from private dependency 'priv_dep' in public interface
-  --> $DIR/pub-priv1.rs:34:5
+  --> $DIR/pub-priv1.rs:35:5
    |
 LL |     type Foo: OtherTrait;
    |     ^^^^^^^^^^^^^^^^^^^^^
diff --git a/src/test/ui/rust-2021/prelude2021.rs b/src/test/ui/rust-2021/prelude2021.rs
index 3a9fd693228..a63b6fcf262 100644
--- a/src/test/ui/rust-2021/prelude2021.rs
+++ b/src/test/ui/rust-2021/prelude2021.rs
@@ -1,6 +1,5 @@
 // check-pass
 // edition:2021
-// compile-flags: -Zunstable-options
 
 fn main() {
     let _: u16 = 123i32.try_into().unwrap();
diff --git a/src/test/ui/rust-2021/reserved-prefixes-migration.fixed b/src/test/ui/rust-2021/reserved-prefixes-migration.fixed
index e026f01e93f..eed2f313abe 100644
--- a/src/test/ui/rust-2021/reserved-prefixes-migration.fixed
+++ b/src/test/ui/rust-2021/reserved-prefixes-migration.fixed
@@ -1,6 +1,6 @@
 // check-pass
 // run-rustfix
-// compile-flags: -Z unstable-options --edition 2018
+// edition:2018
 
 #![warn(rust_2021_prefixes_incompatible_syntax)]
 
diff --git a/src/test/ui/rust-2021/reserved-prefixes-migration.rs b/src/test/ui/rust-2021/reserved-prefixes-migration.rs
index d24f2963480..0565db793df 100644
--- a/src/test/ui/rust-2021/reserved-prefixes-migration.rs
+++ b/src/test/ui/rust-2021/reserved-prefixes-migration.rs
@@ -1,6 +1,6 @@
 // check-pass
 // run-rustfix
-// compile-flags: -Z unstable-options --edition 2018
+// edition:2018
 
 #![warn(rust_2021_prefixes_incompatible_syntax)]
 
diff --git a/src/test/ui/suggestions/undeclared-module-alloc.rs b/src/test/ui/suggestions/undeclared-module-alloc.rs
new file mode 100644
index 00000000000..1defa1cef28
--- /dev/null
+++ b/src/test/ui/suggestions/undeclared-module-alloc.rs
@@ -0,0 +1,5 @@
+// edition:2018
+
+use alloc::rc::Rc; //~ ERROR failed to resolve: use of undeclared crate or module `alloc`
+
+fn main() {}
diff --git a/src/test/ui/suggestions/undeclared-module-alloc.stderr b/src/test/ui/suggestions/undeclared-module-alloc.stderr
new file mode 100644
index 00000000000..39169dfa9f7
--- /dev/null
+++ b/src/test/ui/suggestions/undeclared-module-alloc.stderr
@@ -0,0 +1,11 @@
+error[E0433]: failed to resolve: use of undeclared crate or module `alloc`
+  --> $DIR/undeclared-module-alloc.rs:3:5
+   |
+LL | use alloc::rc::Rc;
+   |     ^^^^^ use of undeclared crate or module `alloc`
+   |
+   = help: add `extern crate alloc` to use the `alloc` crate
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0433`.
diff --git a/src/test/ui/unused-crate-deps/extern-loc-missing-loc.rs b/src/test/ui/unused-crate-deps/extern-loc-missing-loc.rs
index 9339a004d3b..6ac558974d0 100644
--- a/src/test/ui/unused-crate-deps/extern-loc-missing-loc.rs
+++ b/src/test/ui/unused-crate-deps/extern-loc-missing-loc.rs
@@ -1,7 +1,7 @@
 // --extern-location with a raw reference
 
 // aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar
+// compile-flags:--extern-location bar -Zunstable-options
 
 #![warn(unused_crate_dependencies)]
 
diff --git a/src/tools/compiletest/src/header.rs b/src/tools/compiletest/src/header.rs
index 98d1ee19f69..5fcaa452ca3 100644
--- a/src/tools/compiletest/src/header.rs
+++ b/src/tools/compiletest/src/header.rs
@@ -242,9 +242,6 @@ impl TestProps {
                 if let Some(edition) = config.parse_edition(ln) {
                     self.compile_flags.push(format!("--edition={}", edition));
                     has_edition = true;
-                    if edition == "2021" {
-                        self.compile_flags.push("-Zunstable-options".to_string());
-                    }
                 }
 
                 config.parse_and_update_revisions(ln, &mut self.revisions);
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index 4470272a9f8..3c85b9076dd 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -1607,9 +1607,6 @@ impl<'test> TestCx<'test> {
                 get_lib_name(&aux_path.trim_end_matches(".rs").replace('-', "_"), is_dylib);
             rustc.arg("--extern").arg(format!("{}={}/{}", aux_name, aux_dir.display(), lib_name));
         }
-        if !self.props.aux_crates.is_empty() {
-            rustc.arg("-Zunstable-options");
-        }
 
         aux_dir
     }
diff --git a/src/tools/rustdoc-js/tester.js b/src/tools/rustdoc-js/tester.js
index bb9cd00f3f5..a673e425dff 100644
--- a/src/tools/rustdoc-js/tester.js
+++ b/src/tools/rustdoc-js/tester.js
@@ -414,7 +414,7 @@ function parseOptions(args) {
         "test_folder": "",
         "test_file": "",
     };
-    var correspondances = {
+    var correspondences = {
         "--resource-suffix": "resource_suffix",
         "--doc-folder": "doc_folder",
         "--test-folder": "test_folder",
@@ -423,17 +423,13 @@ function parseOptions(args) {
     };
 
     for (var i = 0; i < args.length; ++i) {
-        if (args[i] === "--resource-suffix"
-            || args[i] === "--doc-folder"
-            || args[i] === "--test-folder"
-            || args[i] === "--test-file"
-            || args[i] === "--crate-name") {
+        if (correspondences.hasOwnProperty(args[i])) {
             i += 1;
             if (i >= args.length) {
                 console.log("Missing argument after `" + args[i - 1] + "` option.");
                 return null;
             }
-            opts[correspondances[args[i - 1]]] = args[i];
+            opts[correspondences[args[i - 1]]] = args[i];
         } else if (args[i] === "--help") {
             showHelp();
             process.exit(0);