c++: non-dep array list-init w/ non-triv dtor [PR109899]

Message ID 20240108184010.2235409-1-ppalka@redhat.com
State Accepted
Headers
Series c++: non-dep array list-init w/ non-triv dtor [PR109899] |

Checks

Context Check Description
snail/gcc-patch-check success Github commit url

Commit Message

Patrick Palka Jan. 8, 2024, 6:40 p.m. UTC
  Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look
OK for trunk/13/12?

-- >8 --

The get_target_expr call added in r12-7069-g119cea98f66476 causes us
for the below testcase to call build_vec_delete in a template context,
which builds a templated destructor call and checks expr_noexcept_p for
it, which ICEs because the call has templated form.  Much of the work
of build_vec_delete however is code generation and thus will just get
throw away in a template context, including this expr_noexcept_p check
and the code generation guarded by it.  So this patch narrowly fixes this
ICE by assuming the expr_noexcept_p call returns true in a template
context.

	PR c++/109899

gcc/cp/ChangeLog:

	* init.cc (build_vec_delete_1): Assume expr_noexcept_p is true
	in a template context.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp0x/initlist-array21.C: New test.
---
 gcc/cp/init.cc                                |  3 ++-
 gcc/testsuite/g++.dg/cpp0x/initlist-array21.C | 12 ++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
  

Comments

Patrick Palka Jan. 15, 2024, 7:33 p.m. UTC | #1
On Mon, Jan 8, 2024 at 1:40 PM Patrick Palka <ppalka@redhat.com> wrote:
>
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look
> OK for trunk/13/12?

Ping.

>
> -- >8 --
>
> The get_target_expr call added in r12-7069-g119cea98f66476 causes us
> for the below testcase to call build_vec_delete in a template context,
> which builds a templated destructor call and checks expr_noexcept_p for
> it, which ICEs because the call has templated form.  Much of the work
> of build_vec_delete however is code generation and thus will just get
> throw away in a template context, including this expr_noexcept_p check
> and the code generation guarded by it.  So this patch narrowly fixes this
> ICE by assuming the expr_noexcept_p call returns true in a template

... returns false, rather.

> context.
>
>         PR c++/109899
>
> gcc/cp/ChangeLog:
>
>         * init.cc (build_vec_delete_1): Assume expr_noexcept_p is true

.. is false.

>         in a template context.
>
> gcc/testsuite/ChangeLog:
>
>         * g++.dg/cpp0x/initlist-array21.C: New test.
> ---
>  gcc/cp/init.cc                                |  3 ++-
>  gcc/testsuite/g++.dg/cpp0x/initlist-array21.C | 12 ++++++++++++
>  2 files changed, 14 insertions(+), 1 deletion(-)
>  create mode 100644 gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
>
> diff --git a/gcc/cp/init.cc b/gcc/cp/init.cc
> index 09584719ee6..aa0a35a3885 100644
> --- a/gcc/cp/init.cc
> +++ b/gcc/cp/init.cc
> @@ -4155,7 +4155,8 @@ build_vec_delete_1 (location_t loc, tree base, tree maxindex, tree type,
>
>    /* If one destructor throws, keep trying to clean up the rest, unless we're
>       already in a build_vec_init cleanup.  */
> -  if (flag_exceptions && !in_cleanup && !expr_noexcept_p (tmp, tf_none))
> +  if (flag_exceptions && !in_cleanup && !processing_template_decl
> +      && !expr_noexcept_p (tmp, tf_none))
>      {
>        loop = build2 (TRY_CATCH_EXPR, void_type_node, loop,
>                      unshare_expr (loop));
> diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C b/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
> new file mode 100644
> index 00000000000..5e37e3de62a
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
> @@ -0,0 +1,12 @@
> +// PR c++/109899
> +// { dg-do compile { target c++11 } }
> +
> +struct A { A(); ~A(); };
> +
> +template <typename T>
> +using array = T[42];
> +
> +template<class T>
> +void f() {
> +  array<A>{};
> +}
> --
> 2.43.0.254.ga26002b628
>
  
Jason Merrill Jan. 15, 2024, 9:01 p.m. UTC | #2
On 1/8/24 13:40, Patrick Palka wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look
> OK for trunk/13/12?

OK.

> -- >8 --
> 
> The get_target_expr call added in r12-7069-g119cea98f66476 causes us
> for the below testcase to call build_vec_delete in a template context,
> which builds a templated destructor call and checks expr_noexcept_p for
> it, which ICEs because the call has templated form.  Much of the work
> of build_vec_delete however is code generation and thus will just get
> throw away in a template context, including this expr_noexcept_p check
> and the code generation guarded by it.  So this patch narrowly fixes this
> ICE by assuming the expr_noexcept_p call returns true in a template
> context.
> 
> 	PR c++/109899
> 
> gcc/cp/ChangeLog:
> 
> 	* init.cc (build_vec_delete_1): Assume expr_noexcept_p is true
> 	in a template context.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* g++.dg/cpp0x/initlist-array21.C: New test.
> ---
>   gcc/cp/init.cc                                |  3 ++-
>   gcc/testsuite/g++.dg/cpp0x/initlist-array21.C | 12 ++++++++++++
>   2 files changed, 14 insertions(+), 1 deletion(-)
>   create mode 100644 gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
> 
> diff --git a/gcc/cp/init.cc b/gcc/cp/init.cc
> index 09584719ee6..aa0a35a3885 100644
> --- a/gcc/cp/init.cc
> +++ b/gcc/cp/init.cc
> @@ -4155,7 +4155,8 @@ build_vec_delete_1 (location_t loc, tree base, tree maxindex, tree type,
>   
>     /* If one destructor throws, keep trying to clean up the rest, unless we're
>        already in a build_vec_init cleanup.  */
> -  if (flag_exceptions && !in_cleanup && !expr_noexcept_p (tmp, tf_none))
> +  if (flag_exceptions && !in_cleanup && !processing_template_decl
> +      && !expr_noexcept_p (tmp, tf_none))
>       {
>         loop = build2 (TRY_CATCH_EXPR, void_type_node, loop,
>   		     unshare_expr (loop));
> diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C b/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
> new file mode 100644
> index 00000000000..5e37e3de62a
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
> @@ -0,0 +1,12 @@
> +// PR c++/109899
> +// { dg-do compile { target c++11 } }
> +
> +struct A { A(); ~A(); };
> +
> +template <typename T>
> +using array = T[42];
> +
> +template<class T>
> +void f() {
> +  array<A>{};
> +}
  

Patch

diff --git a/gcc/cp/init.cc b/gcc/cp/init.cc
index 09584719ee6..aa0a35a3885 100644
--- a/gcc/cp/init.cc
+++ b/gcc/cp/init.cc
@@ -4155,7 +4155,8 @@  build_vec_delete_1 (location_t loc, tree base, tree maxindex, tree type,
 
   /* If one destructor throws, keep trying to clean up the rest, unless we're
      already in a build_vec_init cleanup.  */
-  if (flag_exceptions && !in_cleanup && !expr_noexcept_p (tmp, tf_none))
+  if (flag_exceptions && !in_cleanup && !processing_template_decl
+      && !expr_noexcept_p (tmp, tf_none))
     {
       loop = build2 (TRY_CATCH_EXPR, void_type_node, loop,
 		     unshare_expr (loop));
diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C b/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
new file mode 100644
index 00000000000..5e37e3de62a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/initlist-array21.C
@@ -0,0 +1,12 @@ 
+// PR c++/109899
+// { dg-do compile { target c++11 } }
+
+struct A { A(); ~A(); };
+
+template <typename T>
+using array = T[42];
+
+template<class T>
+void f() {
+  array<A>{};
+}