From: Marek Polacek <polacek@redhat.com>
Date: Thu, 5 Mar 2020 00:04:31 +0000 (-0500)
Subject: c++: Fix ICE in tsubst_copy with parenthesized expression [PR93299]
X-Git-Tag: releases/gcc-9.3.0~25
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2b5d109ba3af320f65cb0707e8733eeea3c96262;p=thirdparty%2Fgcc.git

c++: Fix ICE in tsubst_copy with parenthesized expression [PR93299]

	PR c++/93299 - ICE in tsubst_copy with parenthesized expression.
	* pt.c (tsubst_copy): Handle a REF_PARENTHESIZED_P VIEW_CONVERT_EXPR.

	* g++.dg/cpp1y/paren5.C: New test.
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 26d9a08d9efd..a9236063159e 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,11 @@
+2020-03-04  Marek Polacek  <polacek@redhat.com>
+
+	Backported from mainline
+	2020-01-24  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/93299 - ICE in tsubst_copy with parenthesized expression.
+	* pt.c (tsubst_copy): Handle a REF_PARENTHESIZED_P VIEW_CONVERT_EXPR.
+
 2020-03-04  Marek Polacek  <polacek@redhat.com>
 
 	Backported from mainline
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 2de9036b6471..43d9660ebda7 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -15834,6 +15834,14 @@ tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
 		  return op;
 		}
 	    }
+	  /* force_paren_expr can also create a VIEW_CONVERT_EXPR.  */
+	  else if (code == VIEW_CONVERT_EXPR && REF_PARENTHESIZED_P (t))
+	    {
+	      op = tsubst_copy (op, args, complain, in_decl);
+	      op = build1 (code, TREE_TYPE (op), op);
+	      REF_PARENTHESIZED_P (op) = true;
+	      return op;
+	    }
 	  /* We shouldn't see any other uses of these in templates.  */
 	  gcc_unreachable ();
 	}
diff --git a/gcc/testsuite/g++.dg/cpp1y/paren5.C b/gcc/testsuite/g++.dg/cpp1y/paren5.C
new file mode 100644
index 000000000000..86a513564656
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/paren5.C
@@ -0,0 +1,12 @@
+// PR c++/93299 - ICE in tsubst_copy with parenthesized expression.
+// { dg-do compile { target c++14 } }
+
+template <typename> struct A {
+  enum { b = 8 };
+};
+
+template <int> struct __attribute__((aligned((A<int>::b)))) D { };
+struct S : D<0> { };
+
+template <int N> struct __attribute__((aligned((A<int>::b) + N))) D2 { };
+struct S2 : D2<0> { };