Rollup of 6 pull requests

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -58,9 +58,22 @@ struct PostExpansionVisitor<'a> {
 }
 
 impl<'a> PostExpansionVisitor<'a> {
-    fn check_abi(&self, abi: ast::StrLit) {
+    fn check_abi(&self, abi: ast::StrLit, constness: ast::Const) {
         let ast::StrLit { symbol_unescaped, span, .. } = abi;
 
+        if let ast::Const::Yes(_) = constness {
+            match symbol_unescaped.as_str() {
+                // Stable
+                "Rust" | "C" => {}
+                abi => gate_feature_post!(
+                    &self,
+                    const_extern_fn,
+                    span,
+                    &format!("`{}` as a `const fn` ABI is unstable", abi)
+                ),
+            }
+        }
+
         match symbol_unescaped.as_str() {
             // Stable
             "Rust" | "C" | "cdecl" | "stdcall" | "fastcall" | "aapcs" | "win64" | "sysv64"
@@ -261,9 +274,9 @@ impl<'a> PostExpansionVisitor<'a> {
         }
     }
 
-    fn check_extern(&self, ext: ast::Extern) {
+    fn check_extern(&self, ext: ast::Extern, constness: ast::Const) {
         if let ast::Extern::Explicit(abi) = ext {
-            self.check_abi(abi);
+            self.check_abi(abi, constness);
         }
     }
 
@@ -437,7 +450,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
         match i.kind {
             ast::ItemKind::ForeignMod(ref foreign_module) => {
                 if let Some(abi) = foreign_module.abi {
-                    self.check_abi(abi);
+                    self.check_abi(abi, ast::Const::No);
                 }
             }
 
@@ -560,7 +573,8 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
     fn visit_ty(&mut self, ty: &'a ast::Ty) {
         match ty.kind {
             ast::TyKind::BareFn(ref bare_fn_ty) => {
-                self.check_extern(bare_fn_ty.ext);
+                // Function pointers cannot be `const`
+                self.check_extern(bare_fn_ty.ext, ast::Const::No);
             }
             ast::TyKind::Never => {
                 gate_feature_post!(&self, never_type, ty.span, "the `!` type is experimental");
@@ -660,18 +674,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
     fn visit_fn(&mut self, fn_kind: FnKind<'a>, span: Span, _: NodeId) {
         if let Some(header) = fn_kind.header() {
             // Stability of const fn methods are covered in `visit_assoc_item` below.
-            self.check_extern(header.ext);
-
-            if let (ast::Const::Yes(_), ast::Extern::Implicit)
-            | (ast::Const::Yes(_), ast::Extern::Explicit(_)) = (header.constness, header.ext)
-            {
-                gate_feature_post!(
-                    &self,
-                    const_extern_fn,
-                    span,
-                    "`const extern fn` definitions are unstable"
-                );
-            }
+            self.check_extern(header.ext, header.constness);
         }
 
         if fn_kind.ctxt() != Some(FnCtxt::Foreign) && fn_kind.decl().c_variadic() {

compiler/rustc_parse/src/parser/ty.rs

@@ -523,6 +523,9 @@ impl<'a> Parser<'a> {
         let decl = self.parse_fn_decl(|_| false, AllowPlus::No, recover_return_sign)?;
         let whole_span = lo.to(self.prev_token.span);
         if let ast::Const::Yes(span) = constness {
+            // If we ever start to allow `const fn()`, then update
+            // feature gating for `#![feature(const_extern_fn)]` to
+            // cover it.
             self.error_fn_ptr_bad_qualifier(whole_span, span, "const");
         }
         if let ast::Async::Yes { span, .. } = asyncness {

compiler/rustc_typeck/src/check/cast.rs

@@ -993,20 +993,33 @@ impl<'a, 'tcx> CastCheck<'tcx> {
                 ));
 
                 let msg = "use `.addr()` to obtain the address of a pointer";
-                if let Ok(snippet) = fcx.tcx.sess.source_map().span_to_snippet(self.expr_span) {
-                    let scalar_cast = match t_c {
-                        ty::cast::IntTy::U(ty::UintTy::Usize) => String::new(),
-                        _ => format!(" as {}", self.cast_ty),
-                    };
+
+                let expr_prec = self.expr.precedence().order();
+                let needs_parens = expr_prec < rustc_ast::util::parser::PREC_POSTFIX;
+
+                let scalar_cast = match t_c {
+                    ty::cast::IntTy::U(ty::UintTy::Usize) => String::new(),
+                    _ => format!(" as {}", self.cast_ty),
+                };
+
+                let cast_span = self.expr_span.shrink_to_hi().to(self.cast_span);
+
+                if needs_parens {
+                    let suggestions = vec![
+                        (self.expr_span.shrink_to_lo(), String::from("(")),
+                        (cast_span, format!(").addr(){scalar_cast}")),
+                    ];
+
+                    err.multipart_suggestion(msg, suggestions, Applicability::MaybeIncorrect);
+                } else {
                     err.span_suggestion(
-                        self.span,
+                        cast_span,
                         msg,
-                        format!("({snippet}).addr(){scalar_cast}"),
-                        Applicability::MaybeIncorrect
+                        format!(".addr(){scalar_cast}"),
+                        Applicability::MaybeIncorrect,
                     );
-                } else {
-                    err.help(msg);
                 }
+
                 err.help(
                     "if you can't comply with strict provenance and need to expose the pointer \
                     provenance you can use `.expose_addr()` instead"
@@ -1028,16 +1041,12 @@ impl<'a, 'tcx> CastCheck<'tcx> {
                     self.expr_ty, self.cast_ty
                 ));
                 let msg = "use `.with_addr()` to adjust a valid pointer in the same allocation, to this address";
-                if let Ok(snippet) = fcx.tcx.sess.source_map().span_to_snippet(self.expr_span) {
-                    err.span_suggestion(
-                        self.span,
-                        msg,
-                        format!("(...).with_addr({snippet})"),
-                        Applicability::HasPlaceholders,
-                    );
-                } else {
-                    err.help(msg);
-                }
+                let suggestions = vec![
+                    (self.expr_span.shrink_to_lo(), String::from("(...).with_addr(")),
+                    (self.expr_span.shrink_to_hi().to(self.cast_span), String::from(")")),
+                ];
+
+                err.multipart_suggestion(msg, suggestions, Applicability::MaybeIncorrect);
                 err.help(
                     "if you can't comply with strict provenance and don't have a pointer with \
                     the correct provenance you can use `std::ptr::from_exposed_addr()` instead"

library/core/src/char/methods.rs

@@ -343,10 +343,10 @@ impl char {
                   without modifying the original"]
     #[inline]
     pub const fn to_digit(self, radix: u32) -> Option<u32> {
-        assert!(radix <= 36, "to_digit: radix is too high (maximum 36)");
         // If not a digit, a number greater than radix will be created.
         let mut digit = (self as u32).wrapping_sub('0' as u32);
         if radix > 10 {
+            assert!(radix <= 36, "to_digit: radix is too high (maximum 36)");
             if digit < 10 {
                 return Some(digit);
             }

src/bootstrap/config.rs

@@ -221,7 +221,7 @@ impl FromStr for LlvmLibunwind {
     }
 }
 
-#[derive(Debug, Copy, Clone, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Copy, Clone, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct TargetSelection {
     pub triple: Interned<String>,
     file: Option<Interned<String>>,
@@ -276,6 +276,12 @@ impl fmt::Display for TargetSelection {
     }
 }
 
+impl fmt::Debug for TargetSelection {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self)
+    }
+}
+
 impl PartialEq<&str> for TargetSelection {
     fn eq(&self, other: &&str) -> bool {
         self.triple == *other

src/etc/htmldocck.py

@@ -285,6 +285,11 @@ def flatten(node):
     return ''.join(acc)
 
 
+def make_xml(text):
+    xml = ET.XML('<xml>%s</xml>' % text)
+    return xml
+
+
 def normalize_xpath(path):
     path = path.replace("{{channel}}", channel)
     if path.startswith('//'):
@@ -401,7 +406,7 @@ def get_tree_count(tree, path):
     return len(tree.findall(path))
 
 
-def check_snapshot(snapshot_name, tree, normalize_to_text):
+def check_snapshot(snapshot_name, actual_tree, normalize_to_text):
     assert rust_test_path.endswith('.rs')
     snapshot_path = '{}.{}.{}'.format(rust_test_path[:-3], snapshot_name, 'html')
     try:
@@ -414,11 +419,15 @@ def check_snapshot(snapshot_name, tree, normalize_to_text):
             raise FailedCheck('No saved snapshot value')
 
     if not normalize_to_text:
-        actual_str = ET.tostring(tree).decode('utf-8')
+        actual_str = ET.tostring(actual_tree).decode('utf-8')
     else:
-        actual_str = flatten(tree)
+        actual_str = flatten(actual_tree)
+
+    if not expected_str \
+        or (not normalize_to_text and
+            not compare_tree(make_xml(actual_str), make_xml(expected_str), stderr)) \
+        or (normalize_to_text and actual_str != expected_str):
 
-    if expected_str != actual_str:
         if bless:
             with open(snapshot_path, 'w') as snapshot_file:
                 snapshot_file.write(actual_str)
@@ -430,6 +439,59 @@ def check_snapshot(snapshot_name, tree, normalize_to_text):
             print()
             raise FailedCheck('Actual snapshot value is different than expected')
 
+
+# Adapted from https://github.com/formencode/formencode/blob/3a1ba9de2fdd494dd945510a4568a3afeddb0b2e/formencode/doctest_xml_compare.py#L72-L120
+def compare_tree(x1, x2, reporter=None):
+    if x1.tag != x2.tag:
+        if reporter:
+            reporter('Tags do not match: %s and %s' % (x1.tag, x2.tag))
+        return False
+    for name, value in x1.attrib.items():
+        if x2.attrib.get(name) != value:
+            if reporter:
+                reporter('Attributes do not match: %s=%r, %s=%r'
+                         % (name, value, name, x2.attrib.get(name)))
+            return False
+    for name in x2.attrib:
+        if name not in x1.attrib:
+            if reporter:
+                reporter('x2 has an attribute x1 is missing: %s'
+                         % name)
+            return False
+    if not text_compare(x1.text, x2.text):
+        if reporter:
+            reporter('text: %r != %r' % (x1.text, x2.text))
+        return False
+    if not text_compare(x1.tail, x2.tail):
+        if reporter:
+            reporter('tail: %r != %r' % (x1.tail, x2.tail))
+        return False
+    cl1 = list(x1)
+    cl2 = list(x2)
+    if len(cl1) != len(cl2):
+        if reporter:
+            reporter('children length differs, %i != %i'
+                     % (len(cl1), len(cl2)))
+        return False
+    i = 0
+    for c1, c2 in zip(cl1, cl2):
+        i += 1
+        if not compare_tree(c1, c2, reporter=reporter):
+            if reporter:
+                reporter('children %i do not match: %s'
+                         % (i, c1.tag))
+            return False
+    return True
+
+
+def text_compare(t1, t2):
+    if not t1 and not t2:
+        return True
+    if t1 == '*' or t2 == '*':
+        return True
+    return (t1 or '').strip() == (t2 or '').strip()
+
+
 def stderr(*args):
     if sys.version_info.major < 3:
         file = codecs.getwriter('utf-8')(sys.stderr)

src/test/ui/consts/const-extern-fn/feature-gate-const_extern_fn.rs

@@ -1,10 +1,13 @@
-// Check that `const extern fn` and `const unsafe extern fn` are feature-gated.
+// Check that `const extern fn` and `const unsafe extern fn` are feature-gated
+// for certain ABIs.
 
-const extern fn foo1() {} //~ ERROR `const extern fn` definitions are unstable
-const extern "C" fn foo2() {} //~ ERROR `const extern fn` definitions are unstable
-const extern "Rust" fn foo3() {} //~ ERROR `const extern fn` definitions are unstable
-const unsafe extern fn bar1() {} //~ ERROR `const extern fn` definitions are unstable
-const unsafe extern "C" fn bar2() {} //~ ERROR `const extern fn` definitions are unstable
-const unsafe extern "Rust" fn bar3() {} //~ ERROR `const extern fn` definitions are unstable
+const extern fn foo1() {}
+const extern "C" fn foo2() {}
+const extern "Rust" fn foo3() {}
+const extern "cdecl" fn foo4() {} //~ ERROR `cdecl` as a `const fn` ABI is unstable
+const unsafe extern fn bar1() {}
+const unsafe extern "C" fn bar2() {}
+const unsafe extern "Rust" fn bar3() {}
+const unsafe extern "cdecl" fn bar4() {} //~ ERROR `cdecl` as a `const fn` ABI is unstable
 
 fn main() {}

src/test/ui/consts/const-extern-fn/feature-gate-const_extern_fn.stderr

@@ -1,57 +1,21 @@
-error[E0658]: `const extern fn` definitions are unstable
-  --> $DIR/feature-gate-const_extern_fn.rs:3:1
+error[E0658]: `cdecl` as a `const fn` ABI is unstable
+  --> $DIR/feature-gate-const_extern_fn.rs:7:14
    |
-LL | const extern fn foo1() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | const extern "cdecl" fn foo4() {}
+   |              ^^^^^^^
    |
    = note: see issue #64926 <https://github.com/rust-lang/rust/issues/64926> for more information
    = help: add `#![feature(const_extern_fn)]` to the crate attributes to enable
 
-error[E0658]: `const extern fn` definitions are unstable
-  --> $DIR/feature-gate-const_extern_fn.rs:4:1
+error[E0658]: `cdecl` as a `const fn` ABI is unstable
+  --> $DIR/feature-gate-const_extern_fn.rs:11:21
    |
-LL | const extern "C" fn foo2() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | const unsafe extern "cdecl" fn bar4() {}
+   |                     ^^^^^^^
    |
    = note: see issue #64926 <https://github.com/rust-lang/rust/issues/64926> for more information
    = help: add `#![feature(const_extern_fn)]` to the crate attributes to enable
 
-error[E0658]: `const extern fn` definitions are unstable
-  --> $DIR/feature-gate-const_extern_fn.rs:5:1
-   |
-LL | const extern "Rust" fn foo3() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: see issue #64926 <https://github.com/rust-lang/rust/issues/64926> for more information
-   = help: add `#![feature(const_extern_fn)]` to the crate attributes to enable
-
-error[E0658]: `const extern fn` definitions are unstable
-  --> $DIR/feature-gate-const_extern_fn.rs:6:1
-   |
-LL | const unsafe extern fn bar1() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: see issue #64926 <https://github.com/rust-lang/rust/issues/64926> for more information
-   = help: add `#![feature(const_extern_fn)]` to the crate attributes to enable
-
-error[E0658]: `const extern fn` definitions are unstable
-  --> $DIR/feature-gate-const_extern_fn.rs:7:1
-   |
-LL | const unsafe extern "C" fn bar2() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: see issue #64926 <https://github.com/rust-lang/rust/issues/64926> for more information
-   = help: add `#![feature(const_extern_fn)]` to the crate attributes to enable
-
-error[E0658]: `const extern fn` definitions are unstable
-  --> $DIR/feature-gate-const_extern_fn.rs:8:1
-   |
-LL | const unsafe extern "Rust" fn bar3() {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: see issue #64926 <https://github.com/rust-lang/rust/issues/64926> for more information
-   = help: add `#![feature(const_extern_fn)]` to the crate attributes to enable
-
-error: aborting due to 6 previous errors
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0658`.

src/test/ui/lint/lint-strict-provenance-fuzzy-casts.stderr

@@ -13,7 +13,7 @@ LL | #![deny(fuzzy_provenance_casts)]
 help: use `.with_addr()` to adjust a valid pointer in the same allocation, to this address
    |
 LL |     let dangling = (...).with_addr(16_usize);
-   |                    ~~~~~~~~~~~~~~~~~~~~~~~~~
+   |                    ++++++++++++++++        ~
 
 error: aborting due to previous error
 

src/test/ui/lint/lint-strict-provenance-lossy-casts.rs

@@ -8,4 +8,11 @@ fn main() {
 
     let addr_32bit = &x as *const u8 as u32;
     //~^ ERROR under strict provenance it is considered bad style to cast pointer `*const u8` to integer `u32`
+
+    // don't add unnecessary parens in the suggestion
+    let ptr = &x as *const u8;
+    let ptr_addr = ptr as usize;
+    //~^ ERROR under strict provenance it is considered bad style to cast pointer `*const u8` to integer `usize`
+    let ptr_addr_32bit = ptr as u32;
+    //~^ ERROR under strict provenance it is considered bad style to cast pointer `*const u8` to integer `u32`
 }