From: Jason Merrill <jason@redhat.com>
To: Nathaniel Shead <nathanieloshead@gmail.com>, gcc-patches@gcc.gnu.org
Cc: Patrick Palka <ppalka@redhat.com>
Subject: Re: [PATCH] c++: Report invalid id-expression in decltype [PR100482]
Date: Tue, 8 Aug 2023 16:04:07 -0400 [thread overview]
Message-ID: <15535b32-d359-985a-a74d-ca8dcc93f9a1@redhat.com> (raw)
In-Reply-To: <ZNGtCxzbJwkSXvCy@Thaum.localdomain>
On 8/7/23 22:48, Nathaniel Shead wrote:
> Sorry, noticed I provided the wrong version of the test. Here is the
> correct version (not relying on 'namespace std' being implicitly
> defined). Bootstrapped + regtested on x86_64-pc-linux-gnu.
Pushed, thanks!
> -- 8< --
>
> This patch ensures that any errors raised by finish_id_expression when
> parsing a decltype expression are properly reported, rather than
> potentially going ignored and causing invalid code to be accepted.
>
> We can also now remove the separate check for templates without args as
> this is also checked for in finish_id_expression.
>
> PR c++/100482
>
> gcc/cp/ChangeLog:
>
> * parser.cc (cp_parser_decltype_expr): Report errors raised by
> finish_id_expression.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/cpp0x/decltype-100482.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> ---
> gcc/cp/parser.cc | 22 ++++++++++----------
> gcc/testsuite/g++.dg/cpp0x/decltype-100482.C | 12 +++++++++++
> 2 files changed, 23 insertions(+), 11 deletions(-)
> create mode 100644 gcc/testsuite/g++.dg/cpp0x/decltype-100482.C
>
> diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> index d7ef5b34d42..119a14d03b9 100644
> --- a/gcc/cp/parser.cc
> +++ b/gcc/cp/parser.cc
> @@ -16506,10 +16506,6 @@ cp_parser_decltype_expr (cp_parser *parser,
> expr = cp_parser_lookup_name_simple (parser, expr,
> id_expr_start_token->location);
>
> - if (expr && TREE_CODE (expr) == TEMPLATE_DECL)
> - /* A template without args is not a complete id-expression. */
> - expr = error_mark_node;
> -
> if (expr
> && expr != error_mark_node
> && TREE_CODE (expr) != TYPE_DECL
> @@ -16530,13 +16526,17 @@ cp_parser_decltype_expr (cp_parser *parser,
> &error_msg,
> id_expr_start_token->location));
>
> - if (expr == error_mark_node)
> - /* We found an id-expression, but it was something that we
> - should not have found. This is an error, not something
> - we can recover from, so note that we found an
> - id-expression and we'll recover as gracefully as
> - possible. */
> - id_expression_or_member_access_p = true;
> + if (error_msg)
> + {
> + /* We found an id-expression, but it was something that we
> + should not have found. This is an error, not something
> + we can recover from, so report the error we found and
> + we'll recover as gracefully as possible. */
> + cp_parser_parse_definitely (parser);
> + cp_parser_error (parser, error_msg);
> + id_expression_or_member_access_p = true;
> + return error_mark_node;
> + }
> }
>
> if (expr
> diff --git a/gcc/testsuite/g++.dg/cpp0x/decltype-100482.C b/gcc/testsuite/g++.dg/cpp0x/decltype-100482.C
> new file mode 100644
> index 00000000000..1df8b162743
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp0x/decltype-100482.C
> @@ -0,0 +1,12 @@
> +// PR c++/100482
> +// { dg-do compile { target c++11 } }
> +
> +namespace N {}
> +decltype(N) x; // { dg-error "expected primary-expression" }
> +
> +struct S {};
> +decltype(S) y; // { dg-error "argument to .decltype. must be an expression" }
> +
> +template <typename T>
> +struct U {};
> +decltype(U) z; // { dg-error "missing template arguments" }
prev parent reply other threads:[~2023-08-08 20:04 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-30 2:00 Nathaniel Shead
2023-05-27 7:11 ` ping: " Nathaniel Shead
2023-06-13 10:13 ` Nathaniel Shead
2023-06-23 16:15 ` Patrick Palka
2023-06-24 13:27 ` Nathaniel Shead
2023-08-08 2:40 ` Nathaniel Shead
2023-08-08 2:48 ` Nathaniel Shead
2023-08-08 20:04 ` Jason Merrill [this message]
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