diff options
Diffstat (limited to 'gcc/cp/constexpr.c')
| -rw-r--r-- | gcc/cp/constexpr.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c index fc4a3f7..218faec 100644 --- a/gcc/cp/constexpr.c +++ b/gcc/cp/constexpr.c @@ -3525,6 +3525,25 @@ cxx_eval_constant_expression (const constexpr_ctx *ctx, tree t, non_constant_p, overflow_p, jump_target); break; + case REQUIRES_EXPR: + /* It's possible to get a requires-expression in a constant + expression. For example: + + template<typename T> concept bool C() { + return requires (T t) { t; }; + } + + template<typename T> requires !C<T>() void f(T); + + Normalization leaves f with the associated constraint + '!requires (T t) { ... }' which is not transformed into + a constraint. */ + if (!processing_template_decl) + return evaluate_constraint_expression (t, NULL_TREE); + else + *non_constant_p = true; + return t; + default: if (STATEMENT_CODE_P (TREE_CODE (t))) { @@ -3897,6 +3916,7 @@ potential_constant_expression_1 (tree t, bool want_rval, bool strict, case PLACEHOLDER_EXPR: case BREAK_STMT: case CONTINUE_STMT: + case REQUIRES_EXPR: return true; case AGGR_INIT_EXPR: |