diff mbox series

c++: DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P cleanups

Message ID 20240808153054.1949621-1-ppalka@redhat.com
State New
Headers show
Series c++: DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P cleanups | expand

Commit Message

Patrick Palka Aug. 8, 2024, 3:30 p.m. UTC 
DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P templates can only appear as part
of a template friend declaration, and in turn get partially instantiated
only from tsubst_friend_function or tsubst_friend_class.  So rather than
having tsubst_template_decl clear the flag, let's leave it up to the
tsubst friend routines to clear it so that template friend handling stays
localized (note that tsubst_friend_function already was clearing it).

Also the template depth comparison test within tsubst_friend_function is
equivalent to DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P since such templates
always have more levels than the class context, and it's not possible to
directly refer to an existing template that has more levels than the
current template context.

gcc/cp/ChangeLog:

	* pt.cc (tsubst_friend_class): Simplify depth comparison test
	in the redeclaration code path to
	DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P.  Clear the flag in the
	new template code path after partial instantiation here ...
	(tsubst_template_decl): ... instead of here.
---
 gcc/cp/pt.cc | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Comments

Jason Merrill Aug. 9, 2024, 5:16 p.m. UTC | #1 
On 8/8/24 11:30 AM, Patrick Palka wrote:
> DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P templates can only appear as part
> of a template friend declaration, and in turn get partially instantiated
> only from tsubst_friend_function or tsubst_friend_class.  So rather than
> having tsubst_template_decl clear the flag, let's leave it up to the
> tsubst friend routines to clear it so that template friend handling stays
> localized (note that tsubst_friend_function already was clearing it).
> 
> Also the template depth comparison test within tsubst_friend_function is
> equivalent to DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P since such templates
> always have more levels than the class context, and it's not possible to
> directly refer to an existing template that has more levels than the
> current template context.

OK.

> gcc/cp/ChangeLog:
> 
> 	* pt.cc (tsubst_friend_class): Simplify depth comparison test
> 	in the redeclaration code path to
> 	DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P.  Clear the flag in the
> 	new template code path after partial instantiation here ...
> 	(tsubst_template_decl): ... instead of here.
> ---
>   gcc/cp/pt.cc | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
> index 677ed7d1289..d468a3037b6 100644
> --- a/gcc/cp/pt.cc
> +++ b/gcc/cp/pt.cc
> @@ -11764,8 +11764,7 @@ tsubst_friend_class (tree friend_tmpl, tree args)
>   	   compatible with the attachment of the friend template.  */
>   	module_may_redeclare (tmpl, friend_tmpl);
>   
> -      if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
> -	  > TMPL_ARGS_DEPTH (args))
> +      if (DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (friend_tmpl))
>   	{
>   	  tree parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
>   					      args, tf_warning_or_error);
> @@ -11807,6 +11806,7 @@ tsubst_friend_class (tree friend_tmpl, tree args)
>   	  CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
>   	  CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
>   	    = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
> +	  DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (tmpl) = false;
>   
>   	  /* Substitute into and set the constraints on the new declaration.  */
>   	  if (tree ci = get_constraints (friend_tmpl))
> @@ -15008,8 +15008,6 @@ tsubst_template_decl (tree t, tree args, tsubst_flags_t complain,
>     if (PRIMARY_TEMPLATE_P (t))
>       DECL_PRIMARY_TEMPLATE (r) = r;
>   
> -  DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (r) = false;
> -
>     if (!lambda_fntype && !class_p)
>       {
>         /* Record this non-type partial instantiation.  */
diff mbox series

Patch

diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 677ed7d1289..d468a3037b6 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -11764,8 +11764,7 @@  tsubst_friend_class (tree friend_tmpl, tree args)
 	   compatible with the attachment of the friend template.  */
 	module_may_redeclare (tmpl, friend_tmpl);
 
-      if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
-	  > TMPL_ARGS_DEPTH (args))
+      if (DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (friend_tmpl))
 	{
 	  tree parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
 					      args, tf_warning_or_error);
@@ -11807,6 +11806,7 @@  tsubst_friend_class (tree friend_tmpl, tree args)
 	  CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
 	  CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
 	    = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
+	  DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (tmpl) = false;
 
 	  /* Substitute into and set the constraints on the new declaration.  */
 	  if (tree ci = get_constraints (friend_tmpl))
@@ -15008,8 +15008,6 @@  tsubst_template_decl (tree t, tree args, tsubst_flags_t complain,
   if (PRIMARY_TEMPLATE_P (t))
     DECL_PRIMARY_TEMPLATE (r) = r;
 
-  DECL_UNINSTANTIATED_TEMPLATE_FRIEND_P (r) = false;
-
   if (!lambda_fntype && !class_p)
     {
       /* Record this non-type partial instantiation.  */