diff --git a/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs b/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs index 3ed434131b292..286473c38e36d 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs @@ -289,6 +289,7 @@ use super::deconstruct_pat::{Constructor, DeconstructedPat, Fields, SplitWildcar use rustc_data_structures::captures::Captures; use rustc_arena::TypedArena; +use rustc_data_structures::stack::ensure_sufficient_stack; use rustc_hir::def_id::DefId; use rustc_hir::HirId; use rustc_middle::ty::{self, Ty, TyCtxt}; @@ -808,8 +809,9 @@ fn is_useful<'p, 'tcx>( // We try each or-pattern branch in turn. let mut matrix = matrix.clone(); for v in v.expand_or_pat() { - let usefulness = - is_useful(cx, &matrix, &v, witness_preference, hir_id, is_under_guard, false); + let usefulness = ensure_sufficient_stack(|| { + is_useful(cx, &matrix, &v, witness_preference, hir_id, is_under_guard, false) + }); ret.extend(usefulness); // If pattern has a guard don't add it to the matrix. if !is_under_guard { @@ -840,8 +842,9 @@ fn is_useful<'p, 'tcx>( // We cache the result of `Fields::wildcards` because it is used a lot. let spec_matrix = start_matrix.specialize_constructor(pcx, &ctor); let v = v.pop_head_constructor(cx, &ctor); - let usefulness = - is_useful(cx, &spec_matrix, &v, witness_preference, hir_id, is_under_guard, false); + let usefulness = ensure_sufficient_stack(|| { + is_useful(cx, &spec_matrix, &v, witness_preference, hir_id, is_under_guard, false) + }); let usefulness = usefulness.apply_constructor(pcx, start_matrix, &ctor); // When all the conditions are met we have a match with a `non_exhaustive` enum diff --git a/src/test/ui/pattern/usefulness/issue-88747.rs b/src/test/ui/pattern/usefulness/issue-88747.rs new file mode 100644 index 0000000000000..948c99f9ce989 --- /dev/null +++ b/src/test/ui/pattern/usefulness/issue-88747.rs @@ -0,0 +1,14 @@ +// check-pass: this used to be a stack overflow because of recursion in `usefulness.rs` + +macro_rules! long_tuple_arg { + ([$($t:tt)*]#$($h:tt)*) => { + long_tuple_arg!{[$($t)*$($t)*]$($h)*} + }; + ([$([$t:tt $y:tt])*]) => { + pub fn _f(($($t,)*): ($($y,)*)) {} + } +} + +long_tuple_arg!{[[_ u8]]########## ###} + +fn main() {}