From: jason <jason@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Tue, 5 Dec 2017 18:05:23 +0000 (+0000)
Subject: 	PR c++/82331 - ICE with variadic partial specialization of auto
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3ead9ac3088b2a39a14973c730d2b56718618acf;p=thirdparty%2Fgcc.git

	PR c++/82331 - ICE with variadic partial specialization of auto

	* pt.c (unify) [TEMPLATE_PARM_INDEX]: Set processing_template_decl
	around call to tsubst.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@255430 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index d5141f038473..122045b35358 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2017-12-05  Jason Merrill  <jason@redhat.com>
+
+	PR c++/82331 - ICE with variadic partial specialization of auto
+	* pt.c (unify) [TEMPLATE_PARM_INDEX]: Set processing_template_decl
+	around call to tsubst.
+
 2017-12-05  Nathan Sidwell  <nathan@acm.org>
 
 	PR c++/83287
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 500ac0c64fee..685f34a735d4 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -20942,7 +20942,9 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
 	 template-parameter exactly, except that a template-argument
 	 deduced from an array bound may be of any integral type.
 	 The non-type parameter might use already deduced type parameters.  */
+      ++processing_template_decl;
       tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
+      --processing_template_decl;
       if (tree a = type_uses_auto (tparm))
 	{
 	  tparm = do_auto_deduction (tparm, arg, a, complain, adc_unify);
diff --git a/gcc/testsuite/g++.dg/cpp1z/nontype-auto13.C b/gcc/testsuite/g++.dg/cpp1z/nontype-auto13.C
new file mode 100644
index 000000000000..2152cef811ec
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/nontype-auto13.C
@@ -0,0 +1,18 @@
+// PR c++/82331
+// { dg-options -std=c++17 }
+
+template <auto>
+class X;
+
+template <typename R, typename... A, R (*F) (A...)>
+class X<F> {
+public:
+    static R call (A... args)
+    {
+        return (*F)(args...);
+    }
+};
+
+int func (int a, int b) { return a + b; }
+
+int test () { return X<&func>::call(1, 2); }