From: Jason Merrill <jason@redhat.com>
Date: Sat, 19 May 2018 22:57:53 +0000 (-0400)
Subject: Avoid ICE on unsupported use of __integer_pack.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=4b950a6d7c620834d77a63ffe2ee9704df0e4cdc;p=gcc.git

Avoid ICE on unsupported use of __integer_pack.

	* pt.c (tsubst_pack_expansion): Sorry rather than abort
	on __integer_pack as subexpression of pattern.

From-SVN: r260404
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index e4fcffca05b..92039fa8e9a 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2018-05-19  Jason Merrill  <jason@redhat.com>
+
+	* pt.c (tsubst_pack_expansion): Sorry rather than abort
+	on __integer_pack as subexpression of pattern.
+
 2018-05-18  Jason Merrill  <jason@redhat.com>
 
 	PR c++/58407 - deprecated implicit copy ops.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 1e4204043bb..81de633b1ee 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -12067,8 +12067,13 @@ tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
 	}
       else if (builtin_pack_call_p (parm_pack))
 	{
-	  /* ??? Support use in other patterns.  */
-	  gcc_assert (parm_pack == pattern);
+	  if (parm_pack != pattern)
+	    {
+	      if (complain & tf_error)
+		sorry ("%qE is not the entire pattern of the pack expansion",
+		       parm_pack);
+	      return error_mark_node;
+	    }
 	  return expand_builtin_pack_call (parm_pack, args,
 					   complain, in_decl);
 	}
diff --git a/gcc/testsuite/g++.dg/ext/integer-pack4.C b/gcc/testsuite/g++.dg/ext/integer-pack4.C
new file mode 100644
index 00000000000..6e5125baab0
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/integer-pack4.C
@@ -0,0 +1,10 @@
+// { dg-additional-options -std=c++17 }
+
+template<int ... Ns> int f() { return (Ns + ...); }
+template<int N> int g() {
+  return f<__integer_pack(N)...>(); // Fine.
+}
+template<int N> int h() {
+  return f<(2*__integer_pack(N))...>(); // { dg-bogus "sorry" "" { xfail *-*-* } }
+}
+int main() { return g<3>()+h<3>(); }