* [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
end of thread, other threads:[~2023-07-27 3:47 UTC | newest] Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 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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