lookup_and_finish_template_variable calls convert_from_reference, which
means for a variable template-id of reference type the function returns
an INDIRECT_REF instead of the bare VAR_DECL. But the downstream logic
of two callers, tsubst_qualified_id and finish_class_member_access_expr,
expect a DECL_P result and so we end up crashing when resolving the
template-id's in the first testcase. (Note that these two callers
eventually call convert_from_reference as appropriate, so this earlier
call seems at best redundant.)
This patch fixes this by pulling out the convert_from_reference call
from lookup_and_finish_template_variable and into the callers that
actually need it, which turns out to be tsubst_copy_and_build (without
it we'd mishandle the second testcase).
Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk?
PR c++/97340
gcc/cp/ChangeLog:
* pt.cc (lookup_and_finish_template_variable): Don't call
convert_from_reference.
(tsubst_copy_and_build) <case TEMPLATE_ID_EXPR>: Call
convert_from_reference on the result of
lookup_and_finish_template_variable.
gcc/testsuite/ChangeLog:
* g++.dg/cpp1y/var-templ80.C: New test.
* g++.dg/cpp1y/var-templ81.C: New test.
---
gcc/cp/pt.cc | 3 ++-
gcc/testsuite/g++.dg/cpp1y/var-templ80.C | 22 ++++++++++++++++++++++
gcc/testsuite/g++.dg/cpp1y/var-templ81.C | 14 ++++++++++++++
3 files changed, 38 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/cpp1y/var-templ80.C
create mode 100644 gcc/testsuite/g++.dg/cpp1y/var-templ81.C
diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index 351fc18b600..9e5b29f3099 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -10394,7 +10394,7 @@ lookup_and_finish_template_variable (tree templ, tree
targs,
complain &= ~tf_partial;
var = finish_template_variable (var, complain);
mark_used (var);
- return convert_from_reference (var);
+ return var;
}
/* If the set of template parameters PARMS contains a template parameter
@@ -20462,6 +20462,7 @@ tsubst_copy_and_build (tree t,
{
tree r = lookup_and_finish_template_variable (templ, targs,
complain);
+ r = convert_from_reference (r);
r = maybe_wrap_with_location (r, EXPR_LOCATION (t));
RETURN (r);
}
diff --git a/gcc/testsuite/g++.dg/cpp1y/var-templ80.C
b/gcc/testsuite/g++.dg/cpp1y/var-templ80.C
new file mode 100644
index 00000000000..4439bee8292
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/var-templ80.C
@@ -0,0 +1,22 @@
+// PR c++/97340
+// { dg-do compile { target c++14 } }
+
+template<class>
+struct A {
+ template<class>
+ static constexpr const int& var = 0;
+};
+
+template<class T>
+struct B {
+ static constexpr int x1 = A<T>::template var<int>;
+ static constexpr int y1 = A<T>{}.template var<int>;
+
+ static constexpr int x2 = A<int>::template var<T>;
+ static constexpr int y2 = A<int>{}.template var<T>;
+
+ static constexpr int x3 = A<int>::template var<int>;
+ static constexpr int y3 = A<int>{}.template var<int>;
+};
+
+template struct B<int>;
diff --git a/gcc/testsuite/g++.dg/cpp1y/var-templ81.C
b/gcc/testsuite/g++.dg/cpp1y/var-templ81.C
new file mode 100644
index 00000000000..f9d2e6b1eed
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/var-templ81.C
@@ -0,0 +1,14 @@
+// Verify we don't ICE on an invalid use of unary * for a variable
+// template-id of reference type.
+// { dg-do compile { target c++14 } }
+
+template<class>
+static constexpr const int& var = 0;
+
+template<class T>
+struct B {
+ static constexpr int x = *var<T>; // { dg-error "argument of unary" }
+ static constexpr const int& y = *var<T>; // { dg-error "argument of unary" }
+};
+
+template struct B<int>;
--
2.41.0.rc0.4.g004e0f790f
