| Message ID | 20240612182233.2716062-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: undeclared identifier in requires-clause [PR99678] | expand |
On 6/12/24 14:22, Patrick Palka wrote: > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK > for trunk/14? OK. > -- >8 -- > > Since the terms of a requires-clause are grammatically primary-expressions > rather than e.g. postfix-expressions, it seems we need to explicitly > handle and diagnose the case where a term parses to bare unresolved > unqualified-id, like cp_parser_postfix_expression does, since > cp_parser_primary_expression doesn't do so itself. Otherwise we fail to > reject the first three requires-clauses those below. > > Note that the only users of primary-expression in the C++ grammar are > indeed postfix-expression and constraint-logical-and-expression, so it > seems not so surprising that we need this special handling here. > > PR c++/99678 > > gcc/cp/ChangeLog: > > * parser.cc (cp_parser_constraint_primary_expression): Reject > a bare unresolved unqualified-id. > > gcc/testsuite/ChangeLog: > > * g++.dg/cpp2a/concepts-requires38.C: New test. > --- > gcc/cp/parser.cc | 2 ++ > gcc/testsuite/g++.dg/cpp2a/concepts-requires38.C | 14 ++++++++++++++ > 2 files changed, 16 insertions(+) > create mode 100644 gcc/testsuite/g++.dg/cpp2a/concepts-requires38.C > > diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc > index bc4a2359153..0d59f7d2690 100644 > --- a/gcc/cp/parser.cc > +++ b/gcc/cp/parser.cc > @@ -31496,6 +31496,8 @@ cp_parser_constraint_primary_expression (cp_parser *parser, bool lambda_p) > } > if (pce == pce_ok) > { > + if (idk == CP_ID_KIND_UNQUALIFIED && identifier_p (expr)) > + expr = unqualified_name_lookup_error (expr); > cp_lexer_commit_tokens (parser->lexer); > return finish_constraint_primary_expr (expr); > } > diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-requires38.C b/gcc/testsuite/g++.dg/cpp2a/concepts-requires38.C > new file mode 100644 > index 00000000000..663195b79cc > --- /dev/null > +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-requires38.C > @@ -0,0 +1,14 @@ > +// PR c++/99678 > +// { dg-do compile { target c++20 } } > + > +template<class T> > +void f1() requires undeclared_identifier; // { dg-error "not declared" } > + > +template<class T> > +void f2() requires true && undeclared_identifier; // { dg-error "not declared" } > + > +template<class T> > +void f3() requires false || undeclared_identifier; // { dg-error "not declared" } > + > +template<class T> > +void f4() requires undeclared_identifier(T{}); // { dg-error "must be enclosed in parentheses" }
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc index bc4a2359153..0d59f7d2690 100644 --- a/gcc/cp/parser.cc +++ b/gcc/cp/parser.cc @@ -31496,6 +31496,8 @@ cp_parser_constraint_primary_expression (cp_parser *parser, bool lambda_p) } if (pce == pce_ok) { + if (idk == CP_ID_KIND_UNQUALIFIED && identifier_p (expr)) + expr = unqualified_name_lookup_error (expr); cp_lexer_commit_tokens (parser->lexer); return finish_constraint_primary_expr (expr); } diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-requires38.C b/gcc/testsuite/g++.dg/cpp2a/concepts-requires38.C new file mode 100644 index 00000000000..663195b79cc --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-requires38.C @@ -0,0 +1,14 @@ +// PR c++/99678 +// { dg-do compile { target c++20 } } + +template<class T> +void f1() requires undeclared_identifier; // { dg-error "not declared" } + +template<class T> +void f2() requires true && undeclared_identifier; // { dg-error "not declared" } + +template<class T> +void f3() requires false || undeclared_identifier; // { dg-error "not declared" } + +template<class T> +void f4() requires undeclared_identifier(T{}); // { dg-error "must be enclosed in parentheses" }