On 1/31/22 12:27, Patrick Palka wrote:
Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk?
PR c++/104291
gcc/cp/ChangeLog:
* pt.cc (for_each_template_parm_r) <case CONSTRUCTOR>: Don't
walk subtrees if !include_nondeduced_p. Simplify given that
cp_walk_subtrees already walks TYPE_PTRMEMFUNC_FN_TYPE_RAW.
gcc/testsuite/ChangeLog:
* g++.dg/template/partial20.C: New test.
---
gcc/cp/pt.cc | 7 +------
gcc/testsuite/g++.dg/template/partial20.C | 7 +++++++
2 files changed, 8 insertions(+), 6 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/template/partial20.C
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 2f82b167853..feee629f1dd 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -10525,12 +10525,6 @@ for_each_template_parm_r (tree *tp, int
*walk_subtrees, void *d)
*walk_subtrees = 0;
break;
- case CONSTRUCTOR:
- if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
- && pfd->include_nondeduced_p)
- WALK_SUBTREE (TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (t)));
- break;
case INDIRECT_REF:
case COMPONENT_REF:
/* If there's no type, then this thing must be some expression
@@ -10539,6 +10533,7 @@ for_each_template_parm_r (tree *tp, int *walk_subtrees,
void *d)
return error_mark_node;
break;
+ case CONSTRUCTOR:
case TRAIT_EXPR:
case PLUS_EXPR:
case MULT_EXPR:
OK, thanks.
Looking at this area, I'm puzzled by the ancient (!fn) code. AFAICT
nothing calls for_each_template_parm with null FN anymore; it used to be
used by uses_template_parms, until r76647 in 2004. I'll play with
cleaning that up.
diff --git a/gcc/testsuite/g++.dg/template/partial20.C
b/gcc/testsuite/g++.dg/template/partial20.C
new file mode 100644
index 00000000000..161d796b1c2
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/partial20.C
@@ -0,0 +1,7 @@
+// PR c++/104291
+// { dg-do compile { target c++20 } }
+
+struct A { int x; };
+
+template<auto> struct B;
+template<int x> struct B<A{x}> { }; // { dg-error "not deducible" }
