* [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
@ 2023-04-22 6:25 Nathaniel Shead
2023-05-27 7:07 ` ping: " Nathaniel Shead
` (2 more replies)
0 siblings, 3 replies; 9+ messages in thread
From: Nathaniel Shead @ 2023-04-22 6:25 UTC (permalink / raw)
To: gcc-patches; +Cc: Nathaniel Shead
Bootstrapped and tested on x86_64-pc-linux-gnu.
-- 8< --
This patch raises an error early when the decltype(auto) specifier is
used as a parameter of a function. This prevents any issues with an
unexpected tree type later on when performing the call.
PR 103497
gcc/cp/ChangeLog:
* parser.cc (cp_parser_simple_type_specifier): Add check for
decltype(auto) as function parameter.
gcc/testsuite/ChangeLog:
* g++.dg/pr103497.C: New test.
Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
---
gcc/cp/parser.cc | 10 ++++++++++
gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
2 files changed, 17 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/pr103497.C
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index e5f032f2330..1415e07e152 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
&& cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
{
type = saved_checks_value (token->u.tree_check_value);
+ /* Within a function parameter declaration, decltype(auto) is always an
+ error. */
+ if (parser->auto_is_implicit_function_template_parm_p
+ && TREE_CODE (type) == TEMPLATE_TYPE_PARM
+ && AUTO_IS_DECLTYPE (type))
+ {
+ error_at (token->location,
+ "cannot declare a parameter with %<decltype(auto)%>");
+ type = error_mark_node;
+ }
if (decl_specs)
{
cp_parser_set_decl_spec_type (decl_specs, type,
diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
new file mode 100644
index 00000000000..bcd421c2907
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr103497.C
@@ -0,0 +1,7 @@
+// { dg-do compile { target c++14 } }
+
+void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
+
+int main() {
+ foo();
+}
--
2.34.1
^ permalink raw reply [flat|nested] 9+ messages in thread
* ping: [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
2023-04-22 6:25 [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497] Nathaniel Shead
@ 2023-05-27 7:07 ` Nathaniel Shead
2023-06-13 10:14 ` Nathaniel Shead
2023-06-23 15:59 ` Patrick Palka
2 siblings, 0 replies; 9+ messages in thread
From: Nathaniel Shead @ 2023-05-27 7:07 UTC (permalink / raw)
To: gcc-patches
Ping: https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616465.html
On Sat, Apr 22, 2023 at 04:25:13PM +1000, Nathaniel Shead wrote:
> Bootstrapped and tested on x86_64-pc-linux-gnu.
>
> -- 8< --
>
> This patch raises an error early when the decltype(auto) specifier is
> used as a parameter of a function. This prevents any issues with an
> unexpected tree type later on when performing the call.
>
> PR 103497
>
> gcc/cp/ChangeLog:
>
> * parser.cc (cp_parser_simple_type_specifier): Add check for
> decltype(auto) as function parameter.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/pr103497.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> ---
> gcc/cp/parser.cc | 10 ++++++++++
> gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
> 2 files changed, 17 insertions(+)
> create mode 100644 gcc/testsuite/g++.dg/pr103497.C
>
> diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> index e5f032f2330..1415e07e152 100644
> --- a/gcc/cp/parser.cc
> +++ b/gcc/cp/parser.cc
> @@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
> && cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
> {
> type = saved_checks_value (token->u.tree_check_value);
> + /* Within a function parameter declaration, decltype(auto) is always an
> + error. */
> + if (parser->auto_is_implicit_function_template_parm_p
> + && TREE_CODE (type) == TEMPLATE_TYPE_PARM
> + && AUTO_IS_DECLTYPE (type))
> + {
> + error_at (token->location,
> + "cannot declare a parameter with %<decltype(auto)%>");
> + type = error_mark_node;
> + }
> if (decl_specs)
> {
> cp_parser_set_decl_spec_type (decl_specs, type,
> diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
> new file mode 100644
> index 00000000000..bcd421c2907
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/pr103497.C
> @@ -0,0 +1,7 @@
> +// { dg-do compile { target c++14 } }
> +
> +void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
> +
> +int main() {
> + foo();
> +}
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
2023-04-22 6:25 [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497] Nathaniel Shead
2023-05-27 7:07 ` ping: " Nathaniel Shead
@ 2023-06-13 10:14 ` Nathaniel Shead
2023-06-23 15:59 ` Patrick Palka
2 siblings, 0 replies; 9+ messages in thread
From: Nathaniel Shead @ 2023-06-13 10:14 UTC (permalink / raw)
To: gcc-patches
(Another) ping.
https://gcc.gnu.org/pipermail/gcc-patches/2023-April/616465.html
On Sat, Apr 22, 2023 at 04:25:13PM +1000, Nathaniel Shead wrote:
> Bootstrapped and tested on x86_64-pc-linux-gnu.
>
> -- 8< --
>
> This patch raises an error early when the decltype(auto) specifier is
> used as a parameter of a function. This prevents any issues with an
> unexpected tree type later on when performing the call.
>
> PR 103497
>
> gcc/cp/ChangeLog:
>
> * parser.cc (cp_parser_simple_type_specifier): Add check for
> decltype(auto) as function parameter.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/pr103497.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> ---
> gcc/cp/parser.cc | 10 ++++++++++
> gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
> 2 files changed, 17 insertions(+)
> create mode 100644 gcc/testsuite/g++.dg/pr103497.C
>
> diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> index e5f032f2330..1415e07e152 100644
> --- a/gcc/cp/parser.cc
> +++ b/gcc/cp/parser.cc
> @@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
> && cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
> {
> type = saved_checks_value (token->u.tree_check_value);
> + /* Within a function parameter declaration, decltype(auto) is always an
> + error. */
> + if (parser->auto_is_implicit_function_template_parm_p
> + && TREE_CODE (type) == TEMPLATE_TYPE_PARM
> + && AUTO_IS_DECLTYPE (type))
> + {
> + error_at (token->location,
> + "cannot declare a parameter with %<decltype(auto)%>");
> + type = error_mark_node;
> + }
> if (decl_specs)
> {
> cp_parser_set_decl_spec_type (decl_specs, type,
> diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
> new file mode 100644
> index 00000000000..bcd421c2907
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/pr103497.C
> @@ -0,0 +1,7 @@
> +// { dg-do compile { target c++14 } }
> +
> +void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
> +
> +int main() {
> + foo();
> +}
> --
> 2.34.1
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
2023-04-22 6:25 [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497] Nathaniel Shead
2023-05-27 7:07 ` ping: " Nathaniel Shead
2023-06-13 10:14 ` Nathaniel Shead
@ 2023-06-23 15:59 ` Patrick Palka
2023-06-24 13:24 ` Nathaniel Shead
2 siblings, 1 reply; 9+ messages in thread
From: Patrick Palka @ 2023-06-23 15:59 UTC (permalink / raw)
To: Nathaniel Shead; +Cc: gcc-patches, jason
Hi,
On Sat, 22 Apr 2023, Nathaniel Shead via Gcc-patches wrote:
> Bootstrapped and tested on x86_64-pc-linux-gnu.
>
> -- 8< --
>
> This patch raises an error early when the decltype(auto) specifier is
> used as a parameter of a function. This prevents any issues with an
> unexpected tree type later on when performing the call.
Thanks very much for the patch! Some minor comments below.
>
> PR 103497
We should include the bug component name when referring to the PR in the
commit message (i.e. PR c++/103497) so that upon pushing the patch the
post-commit hook automatically adds a comment to the PR reffering to the
commit. I could be wrong but AFAIK the hook only performs this when the
component name is included.
>
> gcc/cp/ChangeLog:
>
> * parser.cc (cp_parser_simple_type_specifier): Add check for
> decltype(auto) as function parameter.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/pr103497.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> ---
> gcc/cp/parser.cc | 10 ++++++++++
> gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
> 2 files changed, 17 insertions(+)
> create mode 100644 gcc/testsuite/g++.dg/pr103497.C
>
> diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> index e5f032f2330..1415e07e152 100644
> --- a/gcc/cp/parser.cc
> +++ b/gcc/cp/parser.cc
> @@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
> && cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
> {
> type = saved_checks_value (token->u.tree_check_value);
> + /* Within a function parameter declaration, decltype(auto) is always an
> + error. */
> + if (parser->auto_is_implicit_function_template_parm_p
> + && TREE_CODE (type) == TEMPLATE_TYPE_PARM
We could check is_auto (type) here instead, to avoid any confusion with
checking AUTO_IS_DECLTYPE for a non-auto TEMPLATE_TYPE_PARM.
> + && AUTO_IS_DECLTYPE (type))
> + {
> + error_at (token->location,
> + "cannot declare a parameter with %<decltype(auto)%>");
> + type = error_mark_node;
> + }
> if (decl_specs)
> {
> cp_parser_set_decl_spec_type (decl_specs, type,
> diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
> new file mode 100644
> index 00000000000..bcd421c2907
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/pr103497.C
> @@ -0,0 +1,7 @@
> +// { dg-do compile { target c++14 } }
> +
> +void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
I noticed for
void foo(decltype(auto) arg);
we already issue an identical error from grokdeclarator. Perhaps we could
instead extend the error handling there to detect decltype(auto)... as well,
rather than adding new error handling in cp_parser_simple_type_specifier?
> +
> +int main() {
> + foo();
> +}
> --
> 2.34.1
>
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
2023-06-23 15:59 ` Patrick Palka
@ 2023-06-24 13:24 ` Nathaniel Shead
2023-06-28 17:54 ` Patrick Palka
2023-06-29 17:43 ` Jason Merrill
0 siblings, 2 replies; 9+ messages in thread
From: Nathaniel Shead @ 2023-06-24 13:24 UTC (permalink / raw)
To: Patrick Palka; +Cc: gcc-patches, jason
On Fri, Jun 23, 2023 at 11:59:51AM -0400, Patrick Palka wrote:
> Hi,
>
> On Sat, 22 Apr 2023, Nathaniel Shead via Gcc-patches wrote:
>
> > Bootstrapped and tested on x86_64-pc-linux-gnu.
> >
> > -- 8< --
> >
> > This patch raises an error early when the decltype(auto) specifier is
> > used as a parameter of a function. This prevents any issues with an
> > unexpected tree type later on when performing the call.
>
> Thanks very much for the patch! Some minor comments below.
>
> >
> > PR 103497
>
> We should include the bug component name when referring to the PR in the
> commit message (i.e. PR c++/103497) so that upon pushing the patch the
> post-commit hook automatically adds a comment to the PR reffering to the
> commit. I could be wrong but AFAIK the hook only performs this when the
> component name is included.
Thanks for the review! Fixed.
> >
> > gcc/cp/ChangeLog:
> >
> > * parser.cc (cp_parser_simple_type_specifier): Add check for
> > decltype(auto) as function parameter.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * g++.dg/pr103497.C: New test.
> >
> > Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> > ---
> > gcc/cp/parser.cc | 10 ++++++++++
> > gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
> > 2 files changed, 17 insertions(+)
> > create mode 100644 gcc/testsuite/g++.dg/pr103497.C
> >
> > diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> > index e5f032f2330..1415e07e152 100644
> > --- a/gcc/cp/parser.cc
> > +++ b/gcc/cp/parser.cc
> > @@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
> > && cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
> > {
> > type = saved_checks_value (token->u.tree_check_value);
> > + /* Within a function parameter declaration, decltype(auto) is always an
> > + error. */
> > + if (parser->auto_is_implicit_function_template_parm_p
> > + && TREE_CODE (type) == TEMPLATE_TYPE_PARM
>
> We could check is_auto (type) here instead, to avoid any confusion with
> checking AUTO_IS_DECLTYPE for a non-auto TEMPLATE_TYPE_PARM.
>
> > + && AUTO_IS_DECLTYPE (type))
> > + {
> > + error_at (token->location,
> > + "cannot declare a parameter with %<decltype(auto)%>");
> > + type = error_mark_node;
> > + }
> > if (decl_specs)
> > {
> > cp_parser_set_decl_spec_type (decl_specs, type,
> > diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
> > new file mode 100644
> > index 00000000000..bcd421c2907
> > --- /dev/null
> > +++ b/gcc/testsuite/g++.dg/pr103497.C
> > @@ -0,0 +1,7 @@
> > +// { dg-do compile { target c++14 } }
> > +
> > +void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
>
> I noticed for
>
> void foo(decltype(auto) arg);
>
> we already issue an identical error from grokdeclarator. Perhaps we could
> instead extend the error handling there to detect decltype(auto)... as well,
> rather than adding new error handling in cp_parser_simple_type_specifier?
Ah thanks, I didn't notice this; this simplifies the change a fair bit.
How about this patch instead?
Regtested on x86_64-pc-linux-gnu.
-- 8< --
This patch ensures that checks for usages of 'auto' in function
parameters also consider parameter packs, since 'type_uses_auto' does
not seem to consider this case.
PR c++/103497
gcc/cp/ChangeLog:
* decl.cc (grokdeclarator): Check for decltype(auto) in
parameter pack.
gcc/testsuite/ChangeLog:
* g++.dg/cpp1y/decltype-auto-103497.C: New test.
Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
---
gcc/cp/decl.cc | 3 +++
gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C | 8 ++++++++
2 files changed, 11 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index 60f107d50c4..aaf691fce68 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -14044,6 +14044,9 @@ grokdeclarator (const cp_declarator *declarator,
error ("cannot use %<::%> in parameter declaration");
tree auto_node = type_uses_auto (type);
+ if (!auto_node && parameter_pack_p)
+ auto_node = type_uses_auto (PACK_EXPANSION_PATTERN (type));
+
if (auto_node && !(cxx_dialect >= cxx17 && template_parm_flag))
{
if (cxx_dialect >= cxx14)
diff --git a/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
new file mode 100644
index 00000000000..cedd661710c
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
@@ -0,0 +1,8 @@
+// PR c++/103497
+// { dg-do compile { target c++14 } }
+
+void foo(decltype(auto)... args); // { dg-error "cannot declare a parameter with .decltype.auto.." }
+
+int main() {
+ foo();
+}
--
2.41.0
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
2023-06-24 13:24 ` Nathaniel Shead
@ 2023-06-28 17:54 ` Patrick Palka
2023-06-29 17:43 ` Jason Merrill
1 sibling, 0 replies; 9+ messages in thread
From: Patrick Palka @ 2023-06-28 17:54 UTC (permalink / raw)
To: Nathaniel Shead; +Cc: gcc-patches, jason
On Sat, Jun 24, 2023 at 9:24 AM Nathaniel Shead
<nathanieloshead@gmail.com> wrote:
>
> On Fri, Jun 23, 2023 at 11:59:51AM -0400, Patrick Palka wrote:
> > Hi,
> >
> > On Sat, 22 Apr 2023, Nathaniel Shead via Gcc-patches wrote:
> >
> > > Bootstrapped and tested on x86_64-pc-linux-gnu.
> > >
> > > -- 8< --
> > >
> > > This patch raises an error early when the decltype(auto) specifier is
> > > used as a parameter of a function. This prevents any issues with an
> > > unexpected tree type later on when performing the call.
> >
> > Thanks very much for the patch! Some minor comments below.
> >
> > >
> > > PR 103497
> >
> > We should include the bug component name when referring to the PR in the
> > commit message (i.e. PR c++/103497) so that upon pushing the patch the
> > post-commit hook automatically adds a comment to the PR reffering to the
> > commit. I could be wrong but AFAIK the hook only performs this when the
> > component name is included.
>
> Thanks for the review! Fixed.
>
> > >
> > > gcc/cp/ChangeLog:
> > >
> > > * parser.cc (cp_parser_simple_type_specifier): Add check for
> > > decltype(auto) as function parameter.
> > >
> > > gcc/testsuite/ChangeLog:
> > >
> > > * g++.dg/pr103497.C: New test.
> > >
> > > Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> > > ---
> > > gcc/cp/parser.cc | 10 ++++++++++
> > > gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
> > > 2 files changed, 17 insertions(+)
> > > create mode 100644 gcc/testsuite/g++.dg/pr103497.C
> > >
> > > diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> > > index e5f032f2330..1415e07e152 100644
> > > --- a/gcc/cp/parser.cc
> > > +++ b/gcc/cp/parser.cc
> > > @@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
> > > && cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
> > > {
> > > type = saved_checks_value (token->u.tree_check_value);
> > > + /* Within a function parameter declaration, decltype(auto) is always an
> > > + error. */
> > > + if (parser->auto_is_implicit_function_template_parm_p
> > > + && TREE_CODE (type) == TEMPLATE_TYPE_PARM
> >
> > We could check is_auto (type) here instead, to avoid any confusion with
> > checking AUTO_IS_DECLTYPE for a non-auto TEMPLATE_TYPE_PARM.
> >
> > > + && AUTO_IS_DECLTYPE (type))
> > > + {
> > > + error_at (token->location,
> > > + "cannot declare a parameter with %<decltype(auto)%>");
> > > + type = error_mark_node;
> > > + }
> > > if (decl_specs)
> > > {
> > > cp_parser_set_decl_spec_type (decl_specs, type,
> > > diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
> > > new file mode 100644
> > > index 00000000000..bcd421c2907
> > > --- /dev/null
> > > +++ b/gcc/testsuite/g++.dg/pr103497.C
> > > @@ -0,0 +1,7 @@
> > > +// { dg-do compile { target c++14 } }
> > > +
> > > +void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
> >
> > I noticed for
> >
> > void foo(decltype(auto) arg);
> >
> > we already issue an identical error from grokdeclarator. Perhaps we could
> > instead extend the error handling there to detect decltype(auto)... as well,
> > rather than adding new error handling in cp_parser_simple_type_specifier?
>
> Ah thanks, I didn't notice this; this simplifies the change a fair bit.
> How about this patch instead?
LGTM! Though I can't approve the patch myself.
>
> Regtested on x86_64-pc-linux-gnu.
>
> -- 8< --
>
> This patch ensures that checks for usages of 'auto' in function
> parameters also consider parameter packs, since 'type_uses_auto' does
> not seem to consider this case.
>
> PR c++/103497
>
> gcc/cp/ChangeLog:
>
> * decl.cc (grokdeclarator): Check for decltype(auto) in
> parameter pack.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/cpp1y/decltype-auto-103497.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> ---
> gcc/cp/decl.cc | 3 +++
> gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C | 8 ++++++++
> 2 files changed, 11 insertions(+)
> create mode 100644 gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
>
> diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
> index 60f107d50c4..aaf691fce68 100644
> --- a/gcc/cp/decl.cc
> +++ b/gcc/cp/decl.cc
> @@ -14044,6 +14044,9 @@ grokdeclarator (const cp_declarator *declarator,
> error ("cannot use %<::%> in parameter declaration");
>
> tree auto_node = type_uses_auto (type);
> + if (!auto_node && parameter_pack_p)
> + auto_node = type_uses_auto (PACK_EXPANSION_PATTERN (type));
> +
> if (auto_node && !(cxx_dialect >= cxx17 && template_parm_flag))
> {
> if (cxx_dialect >= cxx14)
> diff --git a/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
> new file mode 100644
> index 00000000000..cedd661710c
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
> @@ -0,0 +1,8 @@
> +// PR c++/103497
> +// { dg-do compile { target c++14 } }
> +
> +void foo(decltype(auto)... args); // { dg-error "cannot declare a parameter with .decltype.auto.." }
> +
> +int main() {
> + foo();
> +}
> --
> 2.41.0
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
2023-06-24 13:24 ` Nathaniel Shead
2023-06-28 17:54 ` Patrick Palka
@ 2023-06-29 17:43 ` Jason Merrill
2023-06-30 7:05 ` Nathaniel Shead
1 sibling, 1 reply; 9+ messages in thread
From: Jason Merrill @ 2023-06-29 17:43 UTC (permalink / raw)
To: Nathaniel Shead, Patrick Palka; +Cc: gcc-patches
On 6/24/23 09:24, Nathaniel Shead wrote:
> On Fri, Jun 23, 2023 at 11:59:51AM -0400, Patrick Palka wrote:
>> Hi,
>>
>> On Sat, 22 Apr 2023, Nathaniel Shead via Gcc-patches wrote:
>>
>>> Bootstrapped and tested on x86_64-pc-linux-gnu.
>>>
>>> -- 8< --
>>>
>>> This patch raises an error early when the decltype(auto) specifier is
>>> used as a parameter of a function. This prevents any issues with an
>>> unexpected tree type later on when performing the call.
>>
>> Thanks very much for the patch! Some minor comments below.
>>
>>>
>>> PR 103497
>>
>> We should include the bug component name when referring to the PR in the
>> commit message (i.e. PR c++/103497) so that upon pushing the patch the
>> post-commit hook automatically adds a comment to the PR reffering to the
>> commit. I could be wrong but AFAIK the hook only performs this when the
>> component name is included.
>
> Thanks for the review! Fixed.
>
>>>
>>> gcc/cp/ChangeLog:
>>>
>>> * parser.cc (cp_parser_simple_type_specifier): Add check for
>>> decltype(auto) as function parameter.
>>>
>>> gcc/testsuite/ChangeLog:
>>>
>>> * g++.dg/pr103497.C: New test.
>>>
>>> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
>>> ---
>>> gcc/cp/parser.cc | 10 ++++++++++
>>> gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
>>> 2 files changed, 17 insertions(+)
>>> create mode 100644 gcc/testsuite/g++.dg/pr103497.C
>>>
>>> diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
>>> index e5f032f2330..1415e07e152 100644
>>> --- a/gcc/cp/parser.cc
>>> +++ b/gcc/cp/parser.cc
>>> @@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
>>> && cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
>>> {
>>> type = saved_checks_value (token->u.tree_check_value);
>>> + /* Within a function parameter declaration, decltype(auto) is always an
>>> + error. */
>>> + if (parser->auto_is_implicit_function_template_parm_p
>>> + && TREE_CODE (type) == TEMPLATE_TYPE_PARM
>>
>> We could check is_auto (type) here instead, to avoid any confusion with
>> checking AUTO_IS_DECLTYPE for a non-auto TEMPLATE_TYPE_PARM.
>>
>>> + && AUTO_IS_DECLTYPE (type))
>>> + {
>>> + error_at (token->location,
>>> + "cannot declare a parameter with %<decltype(auto)%>");
>>> + type = error_mark_node;
>>> + }
>>> if (decl_specs)
>>> {
>>> cp_parser_set_decl_spec_type (decl_specs, type,
>>> diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
>>> new file mode 100644
>>> index 00000000000..bcd421c2907
>>> --- /dev/null
>>> +++ b/gcc/testsuite/g++.dg/pr103497.C
>>> @@ -0,0 +1,7 @@
>>> +// { dg-do compile { target c++14 } }
>>> +
>>> +void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
>>
>> I noticed for
>>
>> void foo(decltype(auto) arg);
>>
>> we already issue an identical error from grokdeclarator. Perhaps we could
>> instead extend the error handling there to detect decltype(auto)... as well,
>> rather than adding new error handling in cp_parser_simple_type_specifier?
>
> Ah thanks, I didn't notice this; this simplifies the change a fair bit.
> How about this patch instead?
>
> Regtested on x86_64-pc-linux-gnu.
>
> -- 8< --
>
> This patch ensures that checks for usages of 'auto' in function
> parameters also consider parameter packs, since 'type_uses_auto' does
> not seem to consider this case.
>
> PR c++/103497
>
> gcc/cp/ChangeLog:
>
> * decl.cc (grokdeclarator): Check for decltype(auto) in
> parameter pack.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/cpp1y/decltype-auto-103497.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> ---
> gcc/cp/decl.cc | 3 +++
> gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C | 8 ++++++++
> 2 files changed, 11 insertions(+)
> create mode 100644 gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
>
> diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
> index 60f107d50c4..aaf691fce68 100644
> --- a/gcc/cp/decl.cc
> +++ b/gcc/cp/decl.cc
> @@ -14044,6 +14044,9 @@ grokdeclarator (const cp_declarator *declarator,
> error ("cannot use %<::%> in parameter declaration");
>
> tree auto_node = type_uses_auto (type);
> + if (!auto_node && parameter_pack_p)
> + auto_node = type_uses_auto (PACK_EXPANSION_PATTERN (type));
Hmm, I wonder if type_uses_auto should look into PACK_EXPANSION_PATTERN
itself. Would that break anything?
> +
> if (auto_node && !(cxx_dialect >= cxx17 && template_parm_flag))
> {
> if (cxx_dialect >= cxx14)
> diff --git a/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
> new file mode 100644
> index 00000000000..cedd661710c
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
> @@ -0,0 +1,8 @@
> +// PR c++/103497
> +// { dg-do compile { target c++14 } }
> +
> +void foo(decltype(auto)... args); // { dg-error "cannot declare a parameter with .decltype.auto.." }
> +
> +int main() {
> + foo();
> +}
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
2023-06-29 17:43 ` Jason Merrill
@ 2023-06-30 7:05 ` Nathaniel Shead
2023-07-27 3:47 ` Jason Merrill
0 siblings, 1 reply; 9+ messages in thread
From: Nathaniel Shead @ 2023-06-30 7:05 UTC (permalink / raw)
To: Jason Merrill; +Cc: Patrick Palka, gcc-patches
On Thu, Jun 29, 2023 at 01:43:07PM -0400, Jason Merrill wrote:
> On 6/24/23 09:24, Nathaniel Shead wrote:
> > On Fri, Jun 23, 2023 at 11:59:51AM -0400, Patrick Palka wrote:
> > > Hi,
> > >
> > > On Sat, 22 Apr 2023, Nathaniel Shead via Gcc-patches wrote:
> > >
> > > > Bootstrapped and tested on x86_64-pc-linux-gnu.
> > > >
> > > > -- 8< --
> > > >
> > > > This patch raises an error early when the decltype(auto) specifier is
> > > > used as a parameter of a function. This prevents any issues with an
> > > > unexpected tree type later on when performing the call.
> > >
> > > Thanks very much for the patch! Some minor comments below.
> > >
> > > >
> > > > PR 103497
> > >
> > > We should include the bug component name when referring to the PR in the
> > > commit message (i.e. PR c++/103497) so that upon pushing the patch the
> > > post-commit hook automatically adds a comment to the PR reffering to the
> > > commit. I could be wrong but AFAIK the hook only performs this when the
> > > component name is included.
> >
> > Thanks for the review! Fixed.
> >
> > > >
> > > > gcc/cp/ChangeLog:
> > > >
> > > > * parser.cc (cp_parser_simple_type_specifier): Add check for
> > > > decltype(auto) as function parameter.
> > > >
> > > > gcc/testsuite/ChangeLog:
> > > >
> > > > * g++.dg/pr103497.C: New test.
> > > >
> > > > Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> > > > ---
> > > > gcc/cp/parser.cc | 10 ++++++++++
> > > > gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
> > > > 2 files changed, 17 insertions(+)
> > > > create mode 100644 gcc/testsuite/g++.dg/pr103497.C
> > > >
> > > > diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> > > > index e5f032f2330..1415e07e152 100644
> > > > --- a/gcc/cp/parser.cc
> > > > +++ b/gcc/cp/parser.cc
> > > > @@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
> > > > && cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
> > > > {
> > > > type = saved_checks_value (token->u.tree_check_value);
> > > > + /* Within a function parameter declaration, decltype(auto) is always an
> > > > + error. */
> > > > + if (parser->auto_is_implicit_function_template_parm_p
> > > > + && TREE_CODE (type) == TEMPLATE_TYPE_PARM
> > >
> > > We could check is_auto (type) here instead, to avoid any confusion with
> > > checking AUTO_IS_DECLTYPE for a non-auto TEMPLATE_TYPE_PARM.
> > >
> > > > + && AUTO_IS_DECLTYPE (type))
> > > > + {
> > > > + error_at (token->location,
> > > > + "cannot declare a parameter with %<decltype(auto)%>");
> > > > + type = error_mark_node;
> > > > + }
> > > > if (decl_specs)
> > > > {
> > > > cp_parser_set_decl_spec_type (decl_specs, type,
> > > > diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
> > > > new file mode 100644
> > > > index 00000000000..bcd421c2907
> > > > --- /dev/null
> > > > +++ b/gcc/testsuite/g++.dg/pr103497.C
> > > > @@ -0,0 +1,7 @@
> > > > +// { dg-do compile { target c++14 } }
> > > > +
> > > > +void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
> > >
> > > I noticed for
> > >
> > > void foo(decltype(auto) arg);
> > >
> > > we already issue an identical error from grokdeclarator. Perhaps we could
> > > instead extend the error handling there to detect decltype(auto)... as well,
> > > rather than adding new error handling in cp_parser_simple_type_specifier?
> >
> > Ah thanks, I didn't notice this; this simplifies the change a fair bit.
> > How about this patch instead?
> >
> > Regtested on x86_64-pc-linux-gnu.
> >
> > -- 8< --
> >
> > This patch ensures that checks for usages of 'auto' in function
> > parameters also consider parameter packs, since 'type_uses_auto' does
> > not seem to consider this case.
> >
> > PR c++/103497
> >
> > gcc/cp/ChangeLog:
> >
> > * decl.cc (grokdeclarator): Check for decltype(auto) in
> > parameter pack.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * g++.dg/cpp1y/decltype-auto-103497.C: New test.
> >
> > Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> > ---
> > gcc/cp/decl.cc | 3 +++
> > gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C | 8 ++++++++
> > 2 files changed, 11 insertions(+)
> > create mode 100644 gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
> >
> > diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
> > index 60f107d50c4..aaf691fce68 100644
> > --- a/gcc/cp/decl.cc
> > +++ b/gcc/cp/decl.cc
> > @@ -14044,6 +14044,9 @@ grokdeclarator (const cp_declarator *declarator,
> > error ("cannot use %<::%> in parameter declaration");
> > tree auto_node = type_uses_auto (type);
> > + if (!auto_node && parameter_pack_p)
> > + auto_node = type_uses_auto (PACK_EXPANSION_PATTERN (type));
>
> Hmm, I wonder if type_uses_auto should look into PACK_EXPANSION_PATTERN
> itself. Would that break anything?
I gave that a try and it seems to work fine.
Regtested on x86_64-pc-linux-gnu.
-- 8< --
This patch ensures 'type_uses_auto' also checks for usages of 'auto' in
parameter packs.
PR c++/103497
gcc/cp/ChangeLog:
* pt.cc (type_uses_auto): Check inside parameter packs.
gcc/testsuite/ChangeLog:
* g++.dg/cpp1y/decltype-auto-103497.C: New test.
Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
---
gcc/cp/pt.cc | 7 ++++++-
gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C | 8 ++++++++
2 files changed, 14 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 2345a18becc..2a3ba5ab67d 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -31083,7 +31083,12 @@ type_uses_auto (tree type)
{
if (type == NULL_TREE)
return NULL_TREE;
- else if (flag_concepts_ts)
+
+ /* For parameter packs, check the contents of the pack. */
+ if (PACK_EXPANSION_P (type))
+ type = PACK_EXPANSION_PATTERN (type);
+
+ if (flag_concepts_ts)
{
/* The Concepts TS allows multiple autos in one type-specifier; just
return the first one we find, do_auto_deduction will collect all of
diff --git a/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
new file mode 100644
index 00000000000..cedd661710c
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
@@ -0,0 +1,8 @@
+// PR c++/103497
+// { dg-do compile { target c++14 } }
+
+void foo(decltype(auto)... args); // { dg-error "cannot declare a parameter with .decltype.auto.." }
+
+int main() {
+ foo();
+}
--
2.41.0
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497]
2023-06-30 7:05 ` Nathaniel Shead
@ 2023-07-27 3:47 ` Jason Merrill
0 siblings, 0 replies; 9+ messages in thread
From: Jason Merrill @ 2023-07-27 3:47 UTC (permalink / raw)
To: Nathaniel Shead; +Cc: Patrick Palka, gcc-patches
On 6/30/23 03:05, Nathaniel Shead wrote:
> On Thu, Jun 29, 2023 at 01:43:07PM -0400, Jason Merrill wrote:
>> On 6/24/23 09:24, Nathaniel Shead wrote:
>>> On Fri, Jun 23, 2023 at 11:59:51AM -0400, Patrick Palka wrote:
>>>> Hi,
>>>>
>>>> On Sat, 22 Apr 2023, Nathaniel Shead via Gcc-patches wrote:
>>>>
>>>>> Bootstrapped and tested on x86_64-pc-linux-gnu.
>>>>>
>>>>> -- 8< --
>>>>>
>>>>> This patch raises an error early when the decltype(auto) specifier is
>>>>> used as a parameter of a function. This prevents any issues with an
>>>>> unexpected tree type later on when performing the call.
>>>>
>>>> Thanks very much for the patch! Some minor comments below.
>>>>
>>>>>
>>>>> PR 103497
>>>>
>>>> We should include the bug component name when referring to the PR in the
>>>> commit message (i.e. PR c++/103497) so that upon pushing the patch the
>>>> post-commit hook automatically adds a comment to the PR reffering to the
>>>> commit. I could be wrong but AFAIK the hook only performs this when the
>>>> component name is included.
>>>
>>> Thanks for the review! Fixed.
>>>
>>>>>
>>>>> gcc/cp/ChangeLog:
>>>>>
>>>>> * parser.cc (cp_parser_simple_type_specifier): Add check for
>>>>> decltype(auto) as function parameter.
>>>>>
>>>>> gcc/testsuite/ChangeLog:
>>>>>
>>>>> * g++.dg/pr103497.C: New test.
>>>>>
>>>>> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
>>>>> ---
>>>>> gcc/cp/parser.cc | 10 ++++++++++
>>>>> gcc/testsuite/g++.dg/pr103497.C | 7 +++++++
>>>>> 2 files changed, 17 insertions(+)
>>>>> create mode 100644 gcc/testsuite/g++.dg/pr103497.C
>>>>>
>>>>> diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
>>>>> index e5f032f2330..1415e07e152 100644
>>>>> --- a/gcc/cp/parser.cc
>>>>> +++ b/gcc/cp/parser.cc
>>>>> @@ -19884,6 +19884,16 @@ cp_parser_simple_type_specifier (cp_parser* parser,
>>>>> && cp_lexer_peek_nth_token (parser->lexer, 2)->type != CPP_SCOPE)
>>>>> {
>>>>> type = saved_checks_value (token->u.tree_check_value);
>>>>> + /* Within a function parameter declaration, decltype(auto) is always an
>>>>> + error. */
>>>>> + if (parser->auto_is_implicit_function_template_parm_p
>>>>> + && TREE_CODE (type) == TEMPLATE_TYPE_PARM
>>>>
>>>> We could check is_auto (type) here instead, to avoid any confusion with
>>>> checking AUTO_IS_DECLTYPE for a non-auto TEMPLATE_TYPE_PARM.
>>>>
>>>>> + && AUTO_IS_DECLTYPE (type))
>>>>> + {
>>>>> + error_at (token->location,
>>>>> + "cannot declare a parameter with %<decltype(auto)%>");
>>>>> + type = error_mark_node;
>>>>> + }
>>>>> if (decl_specs)
>>>>> {
>>>>> cp_parser_set_decl_spec_type (decl_specs, type,
>>>>> diff --git a/gcc/testsuite/g++.dg/pr103497.C b/gcc/testsuite/g++.dg/pr103497.C
>>>>> new file mode 100644
>>>>> index 00000000000..bcd421c2907
>>>>> --- /dev/null
>>>>> +++ b/gcc/testsuite/g++.dg/pr103497.C
>>>>> @@ -0,0 +1,7 @@
>>>>> +// { dg-do compile { target c++14 } }
>>>>> +
>>>>> +void foo(decltype(auto)... args); // { dg-error "parameter with .decltype.auto..|no parameter packs" }
>>>>
>>>> I noticed for
>>>>
>>>> void foo(decltype(auto) arg);
>>>>
>>>> we already issue an identical error from grokdeclarator. Perhaps we could
>>>> instead extend the error handling there to detect decltype(auto)... as well,
>>>> rather than adding new error handling in cp_parser_simple_type_specifier?
>>>
>>> Ah thanks, I didn't notice this; this simplifies the change a fair bit.
>>> How about this patch instead?
>>>
>>> Regtested on x86_64-pc-linux-gnu.
>>>
>>> -- 8< --
>>>
>>> This patch ensures that checks for usages of 'auto' in function
>>> parameters also consider parameter packs, since 'type_uses_auto' does
>>> not seem to consider this case.
>>>
>>> PR c++/103497
>>>
>>> gcc/cp/ChangeLog:
>>>
>>> * decl.cc (grokdeclarator): Check for decltype(auto) in
>>> parameter pack.
>>>
>>> gcc/testsuite/ChangeLog:
>>>
>>> * g++.dg/cpp1y/decltype-auto-103497.C: New test.
>>>
>>> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
>>> ---
>>> gcc/cp/decl.cc | 3 +++
>>> gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C | 8 ++++++++
>>> 2 files changed, 11 insertions(+)
>>> create mode 100644 gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
>>>
>>> diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
>>> index 60f107d50c4..aaf691fce68 100644
>>> --- a/gcc/cp/decl.cc
>>> +++ b/gcc/cp/decl.cc
>>> @@ -14044,6 +14044,9 @@ grokdeclarator (const cp_declarator *declarator,
>>> error ("cannot use %<::%> in parameter declaration");
>>> tree auto_node = type_uses_auto (type);
>>> + if (!auto_node && parameter_pack_p)
>>> + auto_node = type_uses_auto (PACK_EXPANSION_PATTERN (type));
>>
>> Hmm, I wonder if type_uses_auto should look into PACK_EXPANSION_PATTERN
>> itself. Would that break anything?
>
> I gave that a try and it seems to work fine.
>
> Regtested on x86_64-pc-linux-gnu.
Pushed, thanks.
> -- 8< --
>
> This patch ensures 'type_uses_auto' also checks for usages of 'auto' in
> parameter packs.
>
> PR c++/103497
>
> gcc/cp/ChangeLog:
>
> * pt.cc (type_uses_auto): Check inside parameter packs.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/cpp1y/decltype-auto-103497.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
> ---
> gcc/cp/pt.cc | 7 ++++++-
> gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C | 8 ++++++++
> 2 files changed, 14 insertions(+), 1 deletion(-)
> create mode 100644 gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
>
> diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
> index 2345a18becc..2a3ba5ab67d 100644
> --- a/gcc/cp/pt.cc
> +++ b/gcc/cp/pt.cc
> @@ -31083,7 +31083,12 @@ type_uses_auto (tree type)
> {
> if (type == NULL_TREE)
> return NULL_TREE;
> - else if (flag_concepts_ts)
> +
> + /* For parameter packs, check the contents of the pack. */
> + if (PACK_EXPANSION_P (type))
> + type = PACK_EXPANSION_PATTERN (type);
> +
> + if (flag_concepts_ts)
> {
> /* The Concepts TS allows multiple autos in one type-specifier; just
> return the first one we find, do_auto_deduction will collect all of
> diff --git a/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
> new file mode 100644
> index 00000000000..cedd661710c
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp1y/decltype-auto-103497.C
> @@ -0,0 +1,8 @@
> +// PR c++/103497
> +// { dg-do compile { target c++14 } }
> +
> +void foo(decltype(auto)... args); // { dg-error "cannot declare a parameter with .decltype.auto.." }
> +
> +int main() {
> + foo();
> +}
^ permalink raw reply [flat|nested] 9+ messages in thread
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2023-04-22 6:25 [PATCH] c++: Fix ICE with parameter pack of decltype(auto) [PR103497] Nathaniel Shead
2023-05-27 7:07 ` ping: " Nathaniel Shead
2023-06-13 10:14 ` Nathaniel Shead
2023-06-23 15:59 ` Patrick Palka
2023-06-24 13:24 ` Nathaniel Shead
2023-06-28 17:54 ` Patrick Palka
2023-06-29 17:43 ` Jason Merrill
2023-06-30 7:05 ` Nathaniel Shead
2023-07-27 3:47 ` Jason Merrill
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