Another place we need to look through the VIEW_CONVERT_EXPR we add to make a
use of a class NTTP have const type.
Tested x86_64-pc-linux-gnu, applying to trunk.
* pt.c (deducible_expression): Look through VIEW_CONVERT_EXPR.
---
gcc/cp/pt.c | 2 +-
gcc/testsuite/g++.dg/cpp2a/nontype-class26.C | 13 +++++++++++++
2 files changed, 14 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-class26.C
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index d8ab26ec675..6f658de28ed 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -21183,7 +21183,7 @@ static bool
deducible_expression (tree expr)
{
/* Strip implicit conversions. */
- while (CONVERT_EXPR_P (expr))
+ while (CONVERT_EXPR_P (expr) || TREE_CODE (expr) == VIEW_CONVERT_EXPR)
expr = TREE_OPERAND (expr, 0);
return (TREE_CODE (expr) == TEMPLATE_PARM_INDEX);
}
diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-class26.C
b/gcc/testsuite/g++.dg/cpp2a/nontype-class26.C
new file mode 100644
index 00000000000..315e0ac2309
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/nontype-class26.C
@@ -0,0 +1,13 @@
+// { dg-do compile { target c++2a } }
+
+struct p { unsigned p_ {}; };
+
+template <p i> struct pp {};
+struct qq : public pp <p {}> {};
+
+template <p i> int f (pp <i> const &);
+
+int main ()
+{
+ return f (qq {});
+}
base-commit: 945f2b19497eff52ef44923d291bf0fdba043299
--
2.18.1
