Seems to be fixed by r15-521-g6ad7ca1bb90573.
PR c++/109464
gcc/testsuite/ChangeLog:
* g++.dg/template/explicit-instantiation8.C: New test.
---
.../g++.dg/template/explicit-instantiation8.C | 24 +++++++++++++++++++
1 file changed, 24 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/template/explicit-instantiation8.C
diff --git a/gcc/testsuite/g++.dg/template/explicit-instantiation8.C
b/gcc/testsuite/g++.dg/template/explicit-instantiation8.C
new file mode 100644
index 00000000000..92152a2992e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/explicit-instantiation8.C
@@ -0,0 +1,24 @@
+// PR c++/109464
+// { dg-do compile { target c++11 } }
+
+template<typename T>
+struct shallow
+ {
+ int len;
+ constexpr shallow() : len(0) { }
+ };
+
+template<typename T>
+struct use_shallow
+ {
+ static constexpr shallow<T> s_zstr = { };
+ static_assert(s_zstr.len == 0, "");
+ };
+
+extern template struct shallow<char>;
+extern template struct use_shallow<char>;
+
+template struct shallow<char>;
+template struct use_shallow<char>;
+
+// { dg-final { scan-assembler "_ZN7shallowIcEC2Ev" } }
--
2.46.0.rc0.106.g1c4a234a1c
