diff mbox series

c++: convert_to_void during requires-expr partial subst [PR118060]

Message ID 20241217160412.1029467-1-ppalka@redhat.com
State New
Headers show
Series c++: convert_to_void during requires-expr partial subst [PR118060] | expand

Commit Message

Patrick Palka Dec. 17, 2024, 4:04 p.m. UTC 
Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK
for trunk/14/13?

-- >8 --

Here during partial substitution of the requires-expression (as part of
CTAD constraint rewriting) we segfault from the INDIRECT_REF case of
convert_to_void due *f(u) being type-dependent.  We should just defer
checking convert_to_void until satisfaction.

	PR c++/118060

gcc/cp/ChangeLog:

	* constraint.cc (tsubst_valid_expression_requirement): Don't
	check convert_to_void during partial substitution.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp2a/concepts-requires40.C: New test.
---
 gcc/cp/constraint.cc                             |  4 +++-
 gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C | 12 ++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C

Comments

Patrick Palka Jan. 8, 2025, 5:10 p.m. UTC | #1 
On Tue, Dec 17, 2024 at 11:04 AM Patrick Palka <ppalka@redhat.com> wrote:
>
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK
> for trunk/14/13?

Ping.

>
> -- >8 --
>
> Here during partial substitution of the requires-expression (as part of
> CTAD constraint rewriting) we segfault from the INDIRECT_REF case of
> convert_to_void due *f(u) being type-dependent.  We should just defer
> checking convert_to_void until satisfaction.
>
>         PR c++/118060
>
> gcc/cp/ChangeLog:
>
>         * constraint.cc (tsubst_valid_expression_requirement): Don't
>         check convert_to_void during partial substitution.
>
> gcc/testsuite/ChangeLog:
>
>         * g++.dg/cpp2a/concepts-requires40.C: New test.
> ---
>  gcc/cp/constraint.cc                             |  4 +++-
>  gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C | 12 ++++++++++++
>  2 files changed, 15 insertions(+), 1 deletion(-)
>  create mode 100644 gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C
>
> diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
> index c75982d8009..eb47862fda0 100644
> --- a/gcc/cp/constraint.cc
> +++ b/gcc/cp/constraint.cc
> @@ -1336,7 +1336,9 @@ tsubst_valid_expression_requirement (tree t, tree args, sat_info info)
>  {
>    tsubst_flags_t quiet = info.complain & ~tf_warning_or_error;
>    tree r = tsubst_expr (t, args, quiet, info.in_decl);
> -  if (convert_to_void (r, ICV_STATEMENT, quiet) != error_mark_node)
> +  if (r != error_mark_node
> +      && (processing_template_decl
> +         || convert_to_void (r, ICV_STATEMENT, quiet) != error_mark_node))
>      return r;
>
>    if (info.diagnose_unsatisfaction_p ())
> diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C b/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C
> new file mode 100644
> index 00000000000..918bab410f3
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C
> @@ -0,0 +1,12 @@
> +// PR c++/118060
> +// { dg-do compile { target c++20 } }
> +
> +int* f(int);
> +
> +template<class T>
> +struct A {
> +  template<class U> requires requires (U u) { *f(u); }
> +  A(T, U);
> +};
> +
> +A a{0, 0};
> --
> 2.48.0.rc0
>
Jason Merrill Jan. 8, 2025, 10:02 p.m. UTC | #2 
On 12/17/24 11:04 AM, Patrick Palka wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK
> for trunk/14/13?

OK.

> -- >8 --
> 
> Here during partial substitution of the requires-expression (as part of
> CTAD constraint rewriting) we segfault from the INDIRECT_REF case of
> convert_to_void due *f(u) being type-dependent.  We should just defer
> checking convert_to_void until satisfaction.
> 
> 	PR c++/118060
> 
> gcc/cp/ChangeLog:
> 
> 	* constraint.cc (tsubst_valid_expression_requirement): Don't
> 	check convert_to_void during partial substitution.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* g++.dg/cpp2a/concepts-requires40.C: New test.
> ---
>   gcc/cp/constraint.cc                             |  4 +++-
>   gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C | 12 ++++++++++++
>   2 files changed, 15 insertions(+), 1 deletion(-)
>   create mode 100644 gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C
> 
> diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
> index c75982d8009..eb47862fda0 100644
> --- a/gcc/cp/constraint.cc
> +++ b/gcc/cp/constraint.cc
> @@ -1336,7 +1336,9 @@ tsubst_valid_expression_requirement (tree t, tree args, sat_info info)
>   {
>     tsubst_flags_t quiet = info.complain & ~tf_warning_or_error;
>     tree r = tsubst_expr (t, args, quiet, info.in_decl);
> -  if (convert_to_void (r, ICV_STATEMENT, quiet) != error_mark_node)
> +  if (r != error_mark_node
> +      && (processing_template_decl
> +	  || convert_to_void (r, ICV_STATEMENT, quiet) != error_mark_node))
>       return r;
>   
>     if (info.diagnose_unsatisfaction_p ())
> diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C b/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C
> new file mode 100644
> index 00000000000..918bab410f3
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C
> @@ -0,0 +1,12 @@
> +// PR c++/118060
> +// { dg-do compile { target c++20 } }
> +
> +int* f(int);
> +
> +template<class T>
> +struct A {
> +  template<class U> requires requires (U u) { *f(u); }
> +  A(T, U);
> +};
> +
> +A a{0, 0};
diff mbox series

Patch

diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
index c75982d8009..eb47862fda0 100644
--- a/gcc/cp/constraint.cc
+++ b/gcc/cp/constraint.cc
@@ -1336,7 +1336,9 @@  tsubst_valid_expression_requirement (tree t, tree args, sat_info info)
 {
   tsubst_flags_t quiet = info.complain & ~tf_warning_or_error;
   tree r = tsubst_expr (t, args, quiet, info.in_decl);
-  if (convert_to_void (r, ICV_STATEMENT, quiet) != error_mark_node)
+  if (r != error_mark_node
+      && (processing_template_decl
+	  || convert_to_void (r, ICV_STATEMENT, quiet) != error_mark_node))
     return r;
 
   if (info.diagnose_unsatisfaction_p ())
diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C b/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C
new file mode 100644
index 00000000000..918bab410f3
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/concepts-requires40.C
@@ -0,0 +1,12 @@ 
+// PR c++/118060
+// { dg-do compile { target c++20 } }
+
+int* f(int);
+
+template<class T>
+struct A {
+  template<class U> requires requires (U u) { *f(u); }
+  A(T, U);
+};
+
+A a{0, 0};