Auto merge of #100881 - Dylan-DPC:rollup-q9rr658, r=Dylan-DPC

Rollup of 8 pull requests

Successful merges:

 - #98200 (Expand potential inner `Or` pattern for THIR)
 - #99770 (Make some const prop mir-opt tests `unit-test`s)
 - #99957 (Rework Ipv6Addr::is_global to check for global reachability rather than global scope - rebase)
 - #100331 (Guarantee `try_reserve` preserves the contents on error)
 - #100336 (Fix two const_trait_impl issues)
 - #100713 (Convert diagnostics in parser/expr to SessionDiagnostic)
 - #100820 (Use pointer `is_aligned*` methods)
 - #100872 (Add guarantee that Vec::default() does not alloc)

Failed merges:

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

compiler/rustc_error_messages/locales/en-US/parser.ftl

@@ -41,3 +41,112 @@ parser_switch_mut_let_order =
 parser_missing_let_before_mut = missing keyword
 parser_use_let_not_auto = write `let` instead of `auto` to introduce a new variable
 parser_use_let_not_var = write `let` instead of `var` to introduce a new variable
+
+parser_invalid_comparison_operator = invalid comparison operator `{$invalid}`
+    .use_instead = `{$invalid}` is not a valid comparison operator, use `{$correct}`
+    .spaceship_operator_invalid = `<=>` is not a valid comparison operator, use `std::cmp::Ordering`
+
+parser_invalid_logical_operator = `{$incorrect}` is not a logical operator
+    .note = unlike in e.g., python and PHP, `&&` and `||` are used for logical operators
+    .use_amp_amp_for_conjunction = use `&&` to perform logical conjunction
+    .use_pipe_pipe_for_disjunction = use `||` to perform logical disjunction
+
+parser_tilde_is_not_unary_operator = `~` cannot be used as a unary operator
+    .suggestion = use `!` to perform bitwise not
+
+parser_unexpected_token_after_not = unexpected {$negated_desc} after identifier
+    .suggestion = use `!` to perform logical negation
+
+parser_malformed_loop_label = malformed loop label
+    .suggestion = use the correct loop label format
+
+parser_lifetime_in_borrow_expression = borrow expressions cannot be annotated with lifetimes
+    .suggestion = remove the lifetime annotation
+    .label = annotated with lifetime here
+
+parser_field_expression_with_generic = field expressions cannot have generic arguments
+
+parser_macro_invocation_with_qualified_path = macros cannot use qualified paths
+
+parser_unexpected_token_after_label = expected `while`, `for`, `loop` or `{"{"}` after a label
+
+parser_require_colon_after_labeled_expression = labeled expression must be followed by `:`
+    .note = labels are used before loops and blocks, allowing e.g., `break 'label` to them
+    .label = the label
+    .suggestion = add `:` after the label
+
+parser_do_catch_syntax_removed = found removed `do catch` syntax
+    .note = following RFC #2388, the new non-placeholder syntax is `try`
+    .suggestion = replace with the new syntax
+
+parser_float_literal_requires_integer_part = float literals must have an integer part
+    .suggestion = must have an integer part
+
+parser_invalid_int_literal_width = invalid width `{$width}` for integer literal
+    .help = valid widths are 8, 16, 32, 64 and 128
+
+parser_invalid_num_literal_base_prefix = invalid base prefix for number literal
+    .note = base prefixes (`0xff`, `0b1010`, `0o755`) are lowercase
+    .suggestion = try making the prefix lowercase
+
+parser_invalid_num_literal_suffix = invalid suffix `{$suffix}` for number literal
+    .label = invalid suffix `{$suffix}`
+    .help = the suffix must be one of the numeric types (`u32`, `isize`, `f32`, etc.)
+
+parser_invalid_float_literal_width = invalid width `{$width}` for float literal
+    .help = valid widths are 32 and 64
+
+parser_invalid_float_literal_suffix = invalid suffix `{$suffix}` for float literal
+    .label = invalid suffix `{$suffix}`
+    .help = valid suffixes are `f32` and `f64`
+
+parser_int_literal_too_large = integer literal is too large
+
+parser_missing_semicolon_before_array = expected `;`, found `[`
+    .suggestion = consider adding `;` here
+
+parser_invalid_block_macro_segment = cannot use a `block` macro fragment here
+    .label = the `block` fragment is within this context
+
+parser_if_expression_missing_then_block = this `if` expression is missing a block after the condition
+    .add_then_block = add a block here
+    .condition_possibly_unfinished = this binary operation is possibly unfinished
+
+parser_if_expression_missing_condition = missing condition for `if` expression
+    .condition_label = expected condition here
+    .block_label = if this block is the condition of the `if` expression, then it must be followed by another block
+
+parser_expected_expression_found_let = expected expression, found `let` statement
+
+parser_expected_else_block = expected `{"{"}`, found {$first_tok}
+    .label = expected an `if` or a block after this `else`
+    .suggestion = add an `if` if this is the condition of a chained `else if` statement
+
+parser_outer_attribute_not_allowed_on_if_else = outer attributes are not allowed on `if` and `else` branches
+    .branch_label = the attributes are attached to this branch
+    .ctx_label = the branch belongs to this `{$ctx}`
+    .suggestion = remove the attributes
+
+parser_missing_in_in_for_loop = missing `in` in `for` loop
+    .use_in_not_of = try using `in` here instead
+    .add_in = try adding `in` here
+
+parser_missing_comma_after_match_arm = expected `,` following `match` arm
+    .suggestion = missing a comma here to end this `match` arm
+
+parser_catch_after_try = keyword `catch` cannot follow a `try` block
+    .help = try using `match` on the result of the `try` block instead
+
+parser_comma_after_base_struct = cannot use a comma after the base struct
+    .note = the base struct must always be the last field
+    .suggestion = remove this comma
+
+parser_eq_field_init = expected `:`, found `=`
+    .suggestion = replace equals symbol with a colon
+
+parser_dotdotdot = unexpected token: `...`
+    .suggest_exclusive_range = use `..` for an exclusive range
+    .suggest_inclusive_range = or `..=` for an inclusive range
+
+parser_left_arrow_operator = unexpected token: `<-`
+    .suggestion = if you meant to write a comparison against a negative value, add a space in between `<` and `-`

compiler/rustc_mir_build/src/thir/pattern/usefulness.rs

@@ -364,8 +364,8 @@ impl<'a, 'p, 'tcx> fmt::Debug for PatCtxt<'a, 'p, 'tcx> {
 /// A row of a matrix. Rows of len 1 are very common, which is why `SmallVec[_; 2]`
 /// works well.
 #[derive(Clone)]
-struct PatStack<'p, 'tcx> {
-    pats: SmallVec<[&'p DeconstructedPat<'p, 'tcx>; 2]>,
+pub(crate) struct PatStack<'p, 'tcx> {
+    pub(crate) pats: SmallVec<[&'p DeconstructedPat<'p, 'tcx>; 2]>,
 }
 
 impl<'p, 'tcx> PatStack<'p, 'tcx> {
@@ -403,6 +403,21 @@ impl<'p, 'tcx> PatStack<'p, 'tcx> {
         })
     }
 
+    // Recursively expand all patterns into their subpatterns and push each `PatStack` to matrix.
+    fn expand_and_extend<'a>(&'a self, matrix: &mut Matrix<'p, 'tcx>) {
+        if !self.is_empty() && self.head().is_or_pat() {
+            for pat in self.head().iter_fields() {
+                let mut new_patstack = PatStack::from_pattern(pat);
+                new_patstack.pats.extend_from_slice(&self.pats[1..]);
+                if !new_patstack.is_empty() && new_patstack.head().is_or_pat() {
+                    new_patstack.expand_and_extend(matrix);
+                } else if !new_patstack.is_empty() {
+                    matrix.push(new_patstack);
+                }
+            }
+        }
+    }
+
     /// This computes `S(self.head().ctor(), self)`. See top of the file for explanations.
     ///
     /// Structure patterns with a partial wild pattern (Foo { a: 42, .. }) have their missing
@@ -436,7 +451,7 @@ impl<'p, 'tcx> fmt::Debug for PatStack<'p, 'tcx> {
 /// A 2D matrix.
 #[derive(Clone)]
 pub(super) struct Matrix<'p, 'tcx> {
-    patterns: Vec<PatStack<'p, 'tcx>>,
+    pub patterns: Vec<PatStack<'p, 'tcx>>,
 }
 
 impl<'p, 'tcx> Matrix<'p, 'tcx> {
@@ -453,7 +468,7 @@ impl<'p, 'tcx> Matrix<'p, 'tcx> {
     /// expands it.
     fn push(&mut self, row: PatStack<'p, 'tcx>) {
         if !row.is_empty() && row.head().is_or_pat() {
-            self.patterns.extend(row.expand_or_pat());
+            row.expand_and_extend(self);
         } else {
             self.patterns.push(row);
         }