diff --git a/src/bootstrap/dist.rs b/src/bootstrap/dist.rs
index bd012a8..5529658 100644
--- a/src/bootstrap/dist.rs
+++ b/src/bootstrap/dist.rs
@@ -808,6 +808,7 @@
             "llvm-project/lld", "llvm-project\\lld",
             "llvm-project/lldb", "llvm-project\\lldb",
             "llvm-project/llvm", "llvm-project\\llvm",
+            "llvm-project/compiler-rt", "llvm-project\\compiler-rt",
         ];
         if spath.contains("llvm-project") && !spath.ends_with("llvm-project")
             && !LLVM_PROJECTS.iter().any(|path| spath.contains(path))
diff --git a/src/doc/rustc/src/linker-plugin-lto.md b/src/doc/rustc/src/linker-plugin-lto.md
index 2ae726c..6f1bbe6 100644
--- a/src/doc/rustc/src/linker-plugin-lto.md
+++ b/src/doc/rustc/src/linker-plugin-lto.md
@@ -105,5 +105,6 @@
 | Rust 1.34 |     ✗     |     ✓     |
 | Rust 1.35 |     ✗     |     ✓     |
 | Rust 1.36 |     ✗     |     ✓     |
+| Rust 1.37 |     ✗     |     ✓     |
 
 Note that the compatibility policy for this feature might change in the future.
diff --git a/src/libcore/macros.rs b/src/libcore/macros.rs
index f9dc538..680fcd1 100644
--- a/src/libcore/macros.rs
+++ b/src/libcore/macros.rs
@@ -1281,8 +1281,10 @@
     pub macro test($item:item) { /* compiler built-in */ }
 
     /// Attribute macro applied to a function to turn it into a benchmark test.
-    #[unstable(feature = "test", issue = "50297",
-               reason = "`bench` is a part of custom test frameworks which are unstable")]
+    #[cfg_attr(not(boostrap_stdarch_ignore_this), unstable(soft, feature = "test", issue = "50297",
+               reason = "`bench` is a part of custom test frameworks which are unstable"))]
+    #[cfg_attr(boostrap_stdarch_ignore_this, unstable(feature = "test", issue = "50297",
+               reason = "`bench` is a part of custom test frameworks which are unstable"))]
     #[allow_internal_unstable(test, rustc_attrs)]
     #[rustc_builtin_macro]
     #[rustc_macro_transparency = "semitransparent"]
diff --git a/src/librustc/ich/impls_syntax.rs b/src/librustc/ich/impls_syntax.rs
index 5cc8324..daa69ef 100644
--- a/src/librustc/ich/impls_syntax.rs
+++ b/src/librustc/ich/impls_syntax.rs
@@ -136,9 +136,10 @@
                                           hasher: &mut StableHasher<W>) {
         mem::discriminant(self).hash_stable(hcx, hasher);
         match *self {
-            ::syntax::attr::StabilityLevel::Unstable { ref reason, ref issue } => {
+            ::syntax::attr::StabilityLevel::Unstable { ref reason, ref issue, ref is_soft } => {
                 reason.hash_stable(hcx, hasher);
                 issue.hash_stable(hcx, hasher);
+                is_soft.hash_stable(hcx, hasher);
             }
             ::syntax::attr::StabilityLevel::Stable { ref since } => {
                 since.hash_stable(hcx, hasher);
diff --git a/src/librustc/lint/builtin.rs b/src/librustc/lint/builtin.rs
index 6d9a6bb..dd29057 100644
--- a/src/librustc/lint/builtin.rs
+++ b/src/librustc/lint/builtin.rs
@@ -395,6 +395,12 @@
     "reservation of a two-phased borrow conflicts with other shared borrows"
 }
 
+declare_lint! {
+    pub SOFT_UNSTABLE,
+    Deny,
+    "a feature gate that doesn't break dependent crates"
+}
+
 declare_lint_pass! {
     /// Does nothing as a lint pass, but registers some `Lint`s
     /// that are used by other parts of the compiler.
@@ -460,6 +466,7 @@
         NESTED_IMPL_TRAIT,
         MUTABLE_BORROW_RESERVATION_CONFLICT,
         INDIRECT_STRUCTURAL_MATCH,
+        SOFT_UNSTABLE,
     ]
 }
 
diff --git a/src/librustc/middle/stability.rs b/src/librustc/middle/stability.rs
index 5ab762a..0d22c37 100644
--- a/src/librustc/middle/stability.rs
+++ b/src/librustc/middle/stability.rs
@@ -438,6 +438,7 @@
                     level: attr::StabilityLevel::Unstable {
                         reason: Some(Symbol::intern(reason)),
                         issue: 27812,
+                        is_soft: false,
                     },
                     feature: sym::rustc_private,
                     rustc_depr: None,
@@ -480,7 +481,7 @@
 }
 
 pub fn report_unstable(
-    sess: &Session, feature: Symbol, reason: Option<Symbol>, issue: u32, span: Span
+    sess: &Session, feature: Symbol, reason: Option<Symbol>, issue: u32, is_soft: bool, span: Span
 ) {
     let msg = match reason {
         Some(r) => format!("use of unstable library feature '{}': {}", feature, r),
@@ -505,7 +506,13 @@
     let error_id = (DiagnosticMessageId::StabilityId(issue), span_key, msg.clone());
     let fresh = sess.one_time_diagnostics.borrow_mut().insert(error_id);
     if fresh {
-        emit_feature_err(&sess.parse_sess, feature, span, GateIssue::Library(Some(issue)), &msg);
+        if is_soft {
+            sess.buffer_lint(lint::builtin::SOFT_UNSTABLE, CRATE_NODE_ID, span, &msg);
+        } else {
+            emit_feature_err(
+                &sess.parse_sess, feature, span, GateIssue::Library(Some(issue)), &msg
+            );
+        }
     }
 }
 
@@ -621,6 +628,7 @@
         feature: Symbol,
         reason: Option<Symbol>,
         issue: u32,
+        is_soft: bool,
     },
     /// The item does not have the `#[stable]` or `#[unstable]` marker assigned.
     Unmarked,
@@ -720,7 +728,9 @@
         }
 
         match stability {
-            Some(&Stability { level: attr::Unstable { reason, issue }, feature, .. }) => {
+            Some(&Stability {
+                level: attr::Unstable { reason, issue, is_soft }, feature, ..
+            }) => {
                 if span.allows_unstable(feature) {
                     debug!("stability: skipping span={:?} since it is internal", span);
                     return EvalResult::Allow;
@@ -744,7 +754,7 @@
                     }
                 }
 
-                EvalResult::Deny { feature, reason, issue }
+                EvalResult::Deny { feature, reason, issue, is_soft }
             }
             Some(_) => {
                 // Stable APIs are always ok to call and deprecated APIs are
@@ -767,8 +777,8 @@
     pub fn check_stability(self, def_id: DefId, id: Option<HirId>, span: Span) {
         match self.eval_stability(def_id, id, span) {
             EvalResult::Allow => {}
-            EvalResult::Deny { feature, reason, issue } =>
-                report_unstable(self.sess, feature, reason, issue, span),
+            EvalResult::Deny { feature, reason, issue, is_soft } =>
+                report_unstable(self.sess, feature, reason, issue, is_soft, span),
             EvalResult::Unmarked => {
                 // The API could be uncallable for other reasons, for example when a private module
                 // was referenced.
diff --git a/src/librustc_lint/lib.rs b/src/librustc_lint/lib.rs
index 3a540fd..5648f9d 100644
--- a/src/librustc_lint/lib.rs
+++ b/src/librustc_lint/lib.rs
@@ -433,7 +433,12 @@
             id: LintId::of(INDIRECT_STRUCTURAL_MATCH),
             reference: "issue #62411 <https://github.com/rust-lang/rust/issues/62411>",
             edition: None,
-        }
+        },
+        FutureIncompatibleInfo {
+            id: LintId::of(SOFT_UNSTABLE),
+            reference: "issue #64266 <https://github.com/rust-lang/rust/issues/64266>",
+            edition: None,
+        },
         ]);
 
     // Register renamed and removed lints.
diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs
index 4e970ae..6a3bb8b 100644
--- a/src/librustc_mir/build/mod.rs
+++ b/src/librustc_mir/build/mod.rs
@@ -502,7 +502,7 @@
     // This is a special case: some functions have a C abi but are meant to
     // unwind anyway. Don't stop them.
     match unwind_attr {
-        None => true,
+        None => false, // FIXME(#58794)
         Some(UnwindAttr::Allowed) => false,
         Some(UnwindAttr::Aborts) => true,
     }
diff --git a/src/librustc_resolve/macros.rs b/src/librustc_resolve/macros.rs
index 0ab6f19..50ab074 100644
--- a/src/librustc_resolve/macros.rs
+++ b/src/librustc_resolve/macros.rs
@@ -797,10 +797,10 @@
     fn check_stability_and_deprecation(&self, ext: &SyntaxExtension, path: &ast::Path) {
         let span = path.span;
         if let Some(stability) = &ext.stability {
-            if let StabilityLevel::Unstable { reason, issue } = stability.level {
+            if let StabilityLevel::Unstable { reason, issue, is_soft } = stability.level {
                 let feature = stability.feature;
                 if !self.active_features.contains(&feature) && !span.allows_unstable(feature) {
-                    stability::report_unstable(self.session, feature, reason, issue, span);
+                    stability::report_unstable(self.session, feature, reason, issue, is_soft, span);
                 }
             }
             if let Some(depr) = &stability.rustc_depr {
diff --git a/src/librustdoc/passes/check_code_block_syntax.rs b/src/librustdoc/passes/check_code_block_syntax.rs
index 357e17d..67aa014 100644
--- a/src/librustdoc/passes/check_code_block_syntax.rs
+++ b/src/librustdoc/passes/check_code_block_syntax.rs
@@ -69,7 +69,7 @@
                 // We couldn't calculate the span of the markdown block that had the error, so our
                 // diagnostics are going to be a bit lacking.
                 let mut diag = self.cx.sess().struct_span_warn(
-                    super::span_of_attrs(&item.attrs),
+                    super::span_of_attrs(&item.attrs).unwrap_or(item.source.span()),
                     "doc comment contains an invalid Rust code block",
                 );
 
diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
index 5c9fac7..7f4a172 100644
--- a/src/librustdoc/passes/collect_intra_doc_links.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -464,7 +464,7 @@
         }
     };
     let attrs = &item.attrs;
-    let sp = span_of_attrs(attrs);
+    let sp = span_of_attrs(attrs).unwrap_or(item.source.span());
 
     let mut diag = cx.tcx.struct_span_lint_hir(
         lint::builtin::INTRA_DOC_LINK_RESOLUTION_FAILURE,
@@ -516,7 +516,7 @@
         }
     };
     let attrs = &item.attrs;
-    let sp = span_of_attrs(attrs);
+    let sp = span_of_attrs(attrs).unwrap_or(item.source.span());
 
     let mut msg = format!("`{}` is ", path_str);
 
diff --git a/src/librustdoc/passes/mod.rs b/src/librustdoc/passes/mod.rs
index 641a6df..49a34c7 100644
--- a/src/librustdoc/passes/mod.rs
+++ b/src/librustdoc/passes/mod.rs
@@ -339,7 +339,7 @@
     find_testable_code(&dox, &mut tests, ErrorCodes::No);
 
     if check_missing_code == true && tests.found_tests == 0 {
-        let sp = span_of_attrs(&item.attrs).substitute_dummy(item.source.span());
+        let sp = span_of_attrs(&item.attrs).unwrap_or(item.source.span());
         let mut diag = cx.tcx.struct_span_lint_hir(
             lint::builtin::MISSING_DOC_CODE_EXAMPLES,
             hir_id,
@@ -352,20 +352,23 @@
         let mut diag = cx.tcx.struct_span_lint_hir(
             lint::builtin::PRIVATE_DOC_TESTS,
             hir_id,
-            span_of_attrs(&item.attrs),
+            span_of_attrs(&item.attrs).unwrap_or(item.source.span()),
             "Documentation test in private item");
         diag.emit();
     }
 }
 
 /// Returns a span encompassing all the given attributes.
-crate fn span_of_attrs(attrs: &clean::Attributes) -> Span {
+crate fn span_of_attrs(attrs: &clean::Attributes) -> Option<Span> {
     if attrs.doc_strings.is_empty() {
-        return DUMMY_SP;
+        return None;
     }
     let start = attrs.doc_strings[0].span();
+    if start == DUMMY_SP {
+        return None;
+    }
     let end = attrs.doc_strings.last().expect("No doc strings provided").span();
-    start.to(end)
+    Some(start.to(end))
 }
 
 /// Attempts to match a range of bytes from parsed markdown to a `Span` in the source code.
@@ -391,7 +394,7 @@
     let snippet = cx
         .sess()
         .source_map()
-        .span_to_snippet(span_of_attrs(attrs))
+        .span_to_snippet(span_of_attrs(attrs)?)
         .ok()?;
 
     let starting_line = markdown[..md_range.start].matches('\n').count();
@@ -441,10 +444,8 @@
         }
     }
 
-    let sp = span_of_attrs(attrs).from_inner(InnerSpan::new(
+    Some(span_of_attrs(attrs)?.from_inner(InnerSpan::new(
         md_range.start + start_bytes,
         md_range.end + start_bytes + end_bytes,
-    ));
-
-    Some(sp)
+    )))
 }
diff --git a/src/libsyntax/attr/builtin.rs b/src/libsyntax/attr/builtin.rs
index 5fb5137..b5037b7 100644
--- a/src/libsyntax/attr/builtin.rs
+++ b/src/libsyntax/attr/builtin.rs
@@ -154,23 +154,10 @@
 #[derive(RustcEncodable, RustcDecodable, PartialEq, PartialOrd, Copy, Clone, Debug, Eq, Hash)]
 pub enum StabilityLevel {
     // Reason for the current stability level and the relevant rust-lang issue
-    Unstable { reason: Option<Symbol>, issue: u32 },
+    Unstable { reason: Option<Symbol>, issue: u32, is_soft: bool },
     Stable { since: Symbol },
 }
 
-impl Stability {
-    pub fn unstable(feature: Symbol, reason: Option<Symbol>, issue: u32) -> Stability {
-        Stability {
-            level: StabilityLevel::Unstable { reason, issue },
-            feature,
-            rustc_depr: None,
-            const_stability: None,
-            promotable: false,
-            allow_const_fn_ptr: false,
-        }
-    }
-}
-
 impl StabilityLevel {
     pub fn is_unstable(&self) -> bool {
         if let StabilityLevel::Unstable {..} = *self {
@@ -356,19 +343,27 @@
                     let mut feature = None;
                     let mut reason = None;
                     let mut issue = None;
+                    let mut is_soft = false;
                     for meta in metas {
                         if let Some(mi) = meta.meta_item() {
                             match mi.name_or_empty() {
                                 sym::feature => if !get(mi, &mut feature) { continue 'outer },
                                 sym::reason => if !get(mi, &mut reason) { continue 'outer },
                                 sym::issue => if !get(mi, &mut issue) { continue 'outer },
+                                sym::soft => {
+                                    if !mi.is_word() {
+                                        let msg = "`soft` should not have any arguments";
+                                        sess.span_diagnostic.span_err(mi.span, msg);
+                                    }
+                                    is_soft = true;
+                                }
                                 _ => {
                                     handle_errors(
                                         sess,
                                         meta.span(),
                                         AttrError::UnknownMetaItem(
                                             mi.path.to_string(),
-                                            &["feature", "reason", "issue"]
+                                            &["feature", "reason", "issue", "soft"]
                                         ),
                                     );
                                     continue 'outer
@@ -400,7 +395,8 @@
                                                       "incorrect 'issue'");
                                             continue
                                         }
-                                    }
+                                    },
+                                    is_soft,
                                 },
                                 feature,
                                 rustc_depr: None,
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index bda7612..536687b 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -152,6 +152,18 @@
     printer.s.eof()
 }
 
+// This makes comma-separated lists look slightly nicer,
+// and also addresses a specific regression described in issue #63896.
+fn tt_prepend_space(tt: &TokenTree) -> bool {
+    match tt {
+        TokenTree::Token(token) => match token.kind {
+            token::Comma => false,
+            _ => true,
+        }
+        _ => true,
+    }
+}
+
 fn binop_to_string(op: BinOpToken) -> &'static str {
     match op {
         token::Plus     => "+",
@@ -684,7 +696,7 @@
 
     fn print_tts(&mut self, tts: tokenstream::TokenStream, convert_dollar_crate: bool) {
         for (i, tt) in tts.into_trees().enumerate() {
-            if i != 0 {
+            if i != 0 && tt_prepend_space(&tt) {
                 self.space();
             }
             self.print_tt(tt, convert_dollar_crate);
diff --git a/src/libsyntax_pos/symbol.rs b/src/libsyntax_pos/symbol.rs
index 2d95562..e301a06 100644
--- a/src/libsyntax_pos/symbol.rs
+++ b/src/libsyntax_pos/symbol.rs
@@ -623,6 +623,7 @@
         size,
         slice_patterns,
         slicing_syntax,
+        soft,
         Some,
         specialization,
         speed,
diff --git a/src/llvm-project b/src/llvm-project
index 48818e9..71fe7ec 160000
--- a/src/llvm-project
+++ b/src/llvm-project
@@ -1 +1 @@
-Subproject commit 48818e9f5d0f2d5978a9b43ad1a2e8d0b83f6aa0
+Subproject commit 71fe7ec06b85f612fc0e4eb4134c7a7d0f23fac5
diff --git a/src/test/codegen/c-variadic.rs b/src/test/codegen/c-variadic.rs
index 13be5ce..bb90a96 100644
--- a/src/test/codegen/c-variadic.rs
+++ b/src/test/codegen/c-variadic.rs
@@ -2,6 +2,7 @@
 
 #![crate_type = "lib"]
 #![feature(c_variadic)]
+#![feature(unwind_attributes)]
 #![no_std]
 use core::ffi::VaList;
 
@@ -10,6 +11,7 @@
     fn foreign_c_variadic_1(_: VaList, ...);
 }
 
+#[unwind(aborts)] // FIXME(#58794)
 pub unsafe extern "C" fn use_foreign_c_variadic_0() {
     // Ensure that we correctly call foreign C-variadic functions.
     // CHECK: invoke void (i32, ...) @foreign_c_variadic_0(i32 0)
@@ -24,20 +26,24 @@
 
 // Ensure that we do not remove the `va_list` passed to the foreign function when
 // removing the "spoofed" `VaListImpl` that is used by Rust defined C-variadics.
+#[unwind(aborts)] // FIXME(#58794)
 pub unsafe extern "C" fn use_foreign_c_variadic_1_0(ap: VaList) {
     // CHECK: invoke void ({{.*}}*, ...) @foreign_c_variadic_1({{.*}} %ap)
     foreign_c_variadic_1(ap);
 }
 
+#[unwind(aborts)] // FIXME(#58794)
 pub unsafe extern "C" fn use_foreign_c_variadic_1_1(ap: VaList) {
     // CHECK: invoke void ({{.*}}*, ...) @foreign_c_variadic_1({{.*}} %ap, i32 42)
     foreign_c_variadic_1(ap, 42i32);
 }
+#[unwind(aborts)] // FIXME(#58794)
 pub unsafe extern "C" fn use_foreign_c_variadic_1_2(ap: VaList) {
     // CHECK: invoke void ({{.*}}*, ...) @foreign_c_variadic_1({{.*}} %ap, i32 2, i32 42)
     foreign_c_variadic_1(ap, 2i32, 42i32);
 }
 
+#[unwind(aborts)] // FIXME(#58794)
 pub unsafe extern "C" fn use_foreign_c_variadic_1_3(ap: VaList) {
     // CHECK: invoke void ({{.*}}*, ...) @foreign_c_variadic_1({{.*}} %ap, i32 2, i32 42, i32 0)
     foreign_c_variadic_1(ap, 2i32, 42i32, 0i32);
diff --git a/src/test/incremental/hashes/function_interfaces.rs b/src/test/incremental/hashes/function_interfaces.rs
index 84680a5..4515e36 100644
--- a/src/test/incremental/hashes/function_interfaces.rs
+++ b/src/test/incremental/hashes/function_interfaces.rs
@@ -94,7 +94,7 @@
 pub fn make_extern() {}
 
 #[cfg(not(cfail1))]
-#[rustc_clean(cfg = "cfail2", except = "Hir, HirBody, mir_built, typeck_tables_of, fn_sig")]
+#[rustc_clean(cfg = "cfail2", except = "Hir, HirBody, typeck_tables_of, fn_sig")]
 #[rustc_clean(cfg = "cfail3")]
 pub extern "C" fn make_extern() {}
 
diff --git a/src/test/incremental/hashes/inherent_impls.rs b/src/test/incremental/hashes/inherent_impls.rs
index 882383e..538fd2c 100644
--- a/src/test/incremental/hashes/inherent_impls.rs
+++ b/src/test/incremental/hashes/inherent_impls.rs
@@ -263,7 +263,7 @@
 #[rustc_clean(cfg="cfail2")]
 #[rustc_clean(cfg="cfail3")]
 impl Foo {
-    #[rustc_clean(cfg="cfail2", except="Hir,HirBody,mir_built,fn_sig,typeck_tables_of")]
+    #[rustc_clean(cfg="cfail2", except="Hir,HirBody,fn_sig,typeck_tables_of")]
     #[rustc_clean(cfg="cfail3")]
     pub extern fn make_method_extern(&self) { }
 }
diff --git a/src/test/pretty/attr-literals.rs b/src/test/pretty/attr-literals.rs
index bcd6ffa..9db7e27 100644
--- a/src/test/pretty/attr-literals.rs
+++ b/src/test/pretty/attr-literals.rs
@@ -5,10 +5,10 @@
 #![feature(rustc_attrs)]
 
 fn main() {
-    #![rustc_dummy("hi" , 1 , 2 , 1.012 , pi = 3.14 , bye , name ("John"))]
+    #![rustc_dummy("hi", 1, 2, 1.012, pi = 3.14, bye, name ("John"))]
     #[rustc_dummy = 8]
     fn f() { }
 
-    #[rustc_dummy(1 , 2 , 3)]
+    #[rustc_dummy(1, 2, 3)]
     fn g() { }
 }
diff --git a/src/test/pretty/block-comment-wchar.pp b/src/test/pretty/block-comment-wchar.pp
index f15d7cd..9317b36 100644
--- a/src/test/pretty/block-comment-wchar.pp
+++ b/src/test/pretty/block-comment-wchar.pp
@@ -99,8 +99,5 @@
          '\u{2004}', '\u{2005}', '\u{2006}', '\u{2007}', '\u{2008}',
          '\u{2009}', '\u{200A}', '\u{2028}', '\u{2029}', '\u{202F}',
          '\u{205F}', '\u{3000}'];
-    for c in &chars {
-        let ws = c.is_whitespace();
-        println!("{} {}" , c , ws);
-    }
+    for c in &chars { let ws = c.is_whitespace(); println!("{} {}", c, ws); }
 }
diff --git a/src/test/pretty/delimited-token-groups.rs b/src/test/pretty/delimited-token-groups.rs
index 768f27a..7bbb7dc 100644
--- a/src/test/pretty/delimited-token-groups.rs
+++ b/src/test/pretty/delimited-token-groups.rs
@@ -5,7 +5,7 @@
 macro_rules! mac { ($ ($ tt : tt) *) => () }
 
 mac! {
-    struct S { field1 : u8 , field2 : u16 , } impl Clone for S
+    struct S { field1 : u8, field2 : u16, } impl Clone for S
     {
         fn clone () -> S
         {
diff --git a/src/test/pretty/do1.rs b/src/test/pretty/do1.rs
index 7be835c..233ccdb 100644
--- a/src/test/pretty/do1.rs
+++ b/src/test/pretty/do1.rs
@@ -2,4 +2,4 @@
 
 fn f<F>(f: F) where F: Fn(isize) { f(10) }
 
-fn main() { f(|i| { assert_eq!(i , 10) }) }
+fn main() { f(|i| { assert_eq!(i, 10) }) }
diff --git a/src/test/pretty/match-block-expr.rs b/src/test/pretty/match-block-expr.rs
index 0db6574..10903e9 100644
--- a/src/test/pretty/match-block-expr.rs
+++ b/src/test/pretty/match-block-expr.rs
@@ -2,5 +2,5 @@
 
 fn main() {
     let x = match { 5 } { 1 => 5, 2 => 6, _ => 7, };
-    assert_eq!(x , 7);
+    assert_eq!(x, 7);
 }
diff --git a/src/test/rustdoc/auxiliary/through-proc-macro-aux.rs b/src/test/rustdoc/auxiliary/through-proc-macro-aux.rs
new file mode 100644
index 0000000..5c4a01e
--- /dev/null
+++ b/src/test/rustdoc/auxiliary/through-proc-macro-aux.rs
@@ -0,0 +1,20 @@
+// force-host
+// no-prefer-dynamic
+#![crate_type = "proc-macro"]
+#![crate_name="some_macros"]
+
+extern crate proc_macro;
+use proc_macro::TokenStream;
+
+#[proc_macro_attribute]
+pub fn first(_attr: TokenStream, item: TokenStream) -> TokenStream {
+    item // This doesn't erase the spans.
+}
+
+#[proc_macro_attribute]
+pub fn second(_attr: TokenStream, item: TokenStream) -> TokenStream {
+    // Make a new `TokenStream` to erase the spans:
+    let mut out: TokenStream = TokenStream::new();
+    out.extend(item);
+    out
+}
diff --git a/src/test/rustdoc/through-proc-macro.rs b/src/test/rustdoc/through-proc-macro.rs
new file mode 100644
index 0000000..348c9ee
--- /dev/null
+++ b/src/test/rustdoc/through-proc-macro.rs
@@ -0,0 +1,12 @@
+// aux-build:through-proc-macro-aux.rs
+// build-aux-docs
+#![warn(intra_doc_link_resolution_failure)]
+extern crate some_macros;
+
+#[some_macros::second]
+pub enum Boom {
+    /// [Oooops]
+    Bam,
+}
+
+fn main() {}
diff --git a/src/test/ui/abort-on-c-abi.rs b/src/test/ui/abort-on-c-abi.rs
index cd7dd1b..2f08730 100644
--- a/src/test/ui/abort-on-c-abi.rs
+++ b/src/test/ui/abort-on-c-abi.rs
@@ -1,6 +1,7 @@
 // run-pass
 
 #![allow(unused_must_use)]
+#![feature(unwind_attributes)]
 // Since we mark some ABIs as "nounwind" to LLVM, we must make sure that
 // we never unwind through them.
 
@@ -13,6 +14,7 @@
 use std::io;
 use std::process::{Command, Stdio};
 
+#[unwind(aborts)] // FIXME(#58794)
 extern "C" fn panic_in_ffi() {
     panic!("Test");
 }
diff --git a/src/test/ui/feature-gates/bench.rs b/src/test/ui/feature-gates/bench.rs
new file mode 100644
index 0000000..afe4dc7
--- /dev/null
+++ b/src/test/ui/feature-gates/bench.rs
@@ -0,0 +1,5 @@
+#[bench] //~ ERROR use of unstable library feature 'test'
+         //~| WARN this was previously accepted
+fn bench() {}
+
+fn main() {}
diff --git a/src/test/ui/feature-gates/bench.stderr b/src/test/ui/feature-gates/bench.stderr
new file mode 100644
index 0000000..b9e24e9
--- /dev/null
+++ b/src/test/ui/feature-gates/bench.stderr
@@ -0,0 +1,12 @@
+error: use of unstable library feature 'test': `bench` is a part of custom test frameworks which are unstable
+  --> $DIR/bench.rs:1:3
+   |
+LL | #[bench]
+   |   ^^^^^
+   |
+   = note: `#[deny(soft_unstable)]` on by default
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #64266 <https://github.com/rust-lang/rust/issues/64266>
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/macros/macro-first-set.rs b/src/test/ui/macros/macro-first-set.rs
index a21e4cd..34529cd 100644
--- a/src/test/ui/macros/macro-first-set.rs
+++ b/src/test/ui/macros/macro-first-set.rs
@@ -25,7 +25,7 @@
 }
 
 fn test_26444() {
-    assert_eq!("a , b , c , d , e", foo_26444!(a, b; c; d, e));
+    assert_eq!("a, b, c, d, e", foo_26444!(a, b; c; d, e));
     assert_eq!("f", foo_26444!(; f ;));
 }
 
diff --git a/src/test/ui/proc-macro/auxiliary/attr-stmt-expr-rpass.rs b/src/test/ui/proc-macro/auxiliary/attr-stmt-expr-rpass.rs
index d81e16d..f1de370 100644
--- a/src/test/ui/proc-macro/auxiliary/attr-stmt-expr-rpass.rs
+++ b/src/test/ui/proc-macro/auxiliary/attr-stmt-expr-rpass.rs
@@ -17,7 +17,7 @@
 #[proc_macro_attribute]
 pub fn expect_print_stmt(attr: TokenStream, item: TokenStream) -> TokenStream {
     assert!(attr.to_string().is_empty());
-    assert_eq!(item.to_string(), "println!(\"{}\" , string);");
+    assert_eq!(item.to_string(), "println!(\"{}\", string);");
     item
 }
 
@@ -31,7 +31,7 @@
 #[proc_macro_attribute]
 pub fn expect_print_expr(attr: TokenStream, item: TokenStream) -> TokenStream {
     assert!(attr.to_string().is_empty());
-    assert_eq!(item.to_string(), "println!(\"{}\" , string)");
+    assert_eq!(item.to_string(), "println!(\"{}\", string)");
     item
 }
 
diff --git a/src/test/ui/proc-macro/auxiliary/attr-stmt-expr.rs b/src/test/ui/proc-macro/auxiliary/attr-stmt-expr.rs
index 0a82cbe..d2180de 100644
--- a/src/test/ui/proc-macro/auxiliary/attr-stmt-expr.rs
+++ b/src/test/ui/proc-macro/auxiliary/attr-stmt-expr.rs
@@ -17,7 +17,7 @@
 #[proc_macro_attribute]
 pub fn expect_print_stmt(attr: TokenStream, item: TokenStream) -> TokenStream {
     assert!(attr.to_string().is_empty());
-    assert_eq!(item.to_string(), "println!(\"{}\" , string);");
+    assert_eq!(item.to_string(), "println!(\"{}\", string);");
     item
 }
 
@@ -31,7 +31,7 @@
 #[proc_macro_attribute]
 pub fn expect_print_expr(attr: TokenStream, item: TokenStream) -> TokenStream {
     assert!(attr.to_string().is_empty());
-    assert_eq!(item.to_string(), "println!(\"{}\" , string)");
+    assert_eq!(item.to_string(), "println!(\"{}\", string)");
     item
 }