We were crashing because invalid_nontype_parm_type_p allowed _Complex
template parms, but convert_nontype_argument didn't know what to do for
them. Let's just disallow it, people can and should use std::complex
instead.
Tested x86_64-pc-linux-gnu, applying to trunk.
PR c++/100634
gcc/cp/ChangeLog:
* pt.c (invalid_nontype_parm_type_p): Return true for COMPLEX_TYPE.
gcc/testsuite/ChangeLog:
* g++.dg/cpp2a/nontype-complex1.C: New test.
---
gcc/cp/pt.c | 2 ++
gcc/testsuite/g++.dg/cpp2a/nontype-complex1.C | 8 ++++++++
2 files changed, 10 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-complex1.C
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 32cd0b7a6ed..cbd2f3dc338 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -26563,6 +26563,8 @@ invalid_nontype_parm_type_p (tree type, tsubst_flags_t
complain)
else if (cxx_dialect >= cxx11
&& TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
return false;
+ else if (TREE_CODE (type) == COMPLEX_TYPE)
+ /* Fall through. */;
else if (VOID_TYPE_P (type))
/* Fall through. */;
else if (cxx_dialect >= cxx20)
diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-complex1.C
b/gcc/testsuite/g++.dg/cpp2a/nontype-complex1.C
new file mode 100644
index 00000000000..4de2168ef60
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/nontype-complex1.C
@@ -0,0 +1,8 @@
+// PR c++/100634
+// { dg-do compile { target c++20 } }
+// { dg-options "" }
+
+// We could support _Complex template arguments, but better I think to make
+// people use a standard type instead.
+template<_Complex int> struct ComplexInt {}; // { dg-error "not a valid type" }
+using CI = ComplexInt<1 + 3i>;
base-commit: 65f32e5d6bbeb93a7d8d121fd56af6555e16d747
prerequisite-patch-id: ae2039c7381d197d44ea669393e7107448d8e156
--
2.27.0
