[C++ PATCH] [PR87770] test partial specializations for type dependence

[Alexandre Oliva]

When instantiating a partial specialization of a template member
function for a full specialization of a class template, we test
whether the context of variables local to the partial specialization,
i.e., the partial specialization itself, is dependent, and this ICEs
in type_dependent_expression_p, when checking that the function type
isn't type-dependent because it is not in a type-dependent scope.

We shouldn't have got that far: the previous block in
type_dependent_expression_p catches cases in which the function itself
takes template arguments of its own, but it only did so for primary
templates, not for partial specializations.  This patch fixes that.

Regstrapped on x86_64- and i686-linux-gnu.  Ok to install?


for  gcc/cp/ChangeLog

	PR c++/87770
	* pt.c (type_dependent_expression_p): Check partial
	specializations for taking template arguments.

for  gcc/testsuite/ChangeLog

	PR c++/87770
	* g++.dg/pr87770.C: New.
---
 gcc/cp/pt.c                    |    3 ++-
 gcc/testsuite/g++.dg/pr87770.C |   11 +++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/pr87770.C

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index e4f76478f543..fb8993f1959e 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -25607,7 +25607,8 @@ type_dependent_expression_p (tree expression)
 	 that come from the template-id; the template arguments for the
 	 enclosing class do not make it type-dependent unless they are used in
 	 the type of the decl.  */
-      if (PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (expression))
+      if ((PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (expression))
+	   || DECL_TEMPLATE_SPECIALIZATION (DECL_TI_TEMPLATE (expression)))
 	  && (any_dependent_template_arguments_p
 	      (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
 	return true;
diff --git a/gcc/testsuite/g++.dg/pr87770.C b/gcc/testsuite/g++.dg/pr87770.C
new file mode 100644
index 000000000000..69eff4a786fe
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr87770.C
@@ -0,0 +1,11 @@
+// { dg-do compile }
+
+template <typename> struct d {
+  template <typename e> d(e);
+};
+template <> template <typename e> d<int>::d(e);
+template <> template <typename e> d<int>::d(e) {
+  long g;
+  (void)g;
+}
+template d<int>::d(char);


-- 
Alexandre Oliva, freedom fighter   https://FSFLA.org/blogs/lxo
Be the change, be Free!         FSF Latin America board member
GNU Toolchain Engineer                Free Software Evangelist
Hay que enGNUrecerse, pero sin perder la terGNUra jamás-GNUChe