re PR c++/79782 (ICE: tree check: expected tree_list, have void_type in…

re PR c++/79782 (ICE: tree check: expected tree_list, have void_type in emit_mem_initializers, at cp/init.c:1225)

	PR c++/79782
	* init.c (mark_exp_read_r): New function.
	(emit_mem_initializers): Use cp_walk_tree with mark_exp_read_r on
	whole arguments instead of plain mark_exp_read on TREE_LIST values.

	* g++.dg/warn/Wunused-parm-10.C: New test.

From-SVN: r245853

gcc/cp/ChangeLog

+2017-03-02  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/79782
+	* init.c (mark_exp_read_r): New function.
+	(emit_mem_initializers): Use cp_walk_tree with mark_exp_read_r on
+	whole arguments instead of plain mark_exp_read on TREE_LIST values.
+
 2017-03-01  Jason Merrill  <jason@redhat.com>
 
 	Class template argument deduction in new-expression

gcc/cp/init.c

@@ -1127,6 +1127,17 @@ sort_mem_initializers (tree t, tree mem_inits)
   return sorted_inits;
 }
 
+/* Callback for cp_walk_tree to mark all PARM_DECLs in a tree as read.  */
+
+static tree
+mark_exp_read_r (tree *tp, int *, void *)
+{
+  tree t = *tp;
+  if (TREE_CODE (t) == PARM_DECL)
+    mark_exp_read (t);
+  return NULL_TREE;
+}
+
 /* Initialize all bases and members of CURRENT_CLASS_TYPE.  MEM_INITS
    is a TREE_LIST giving the explicit mem-initializer-list for the
    constructor.  The TREE_PURPOSE of each entry is a subobject (a
@@ -1221,8 +1232,7 @@ emit_mem_initializers (tree mem_inits)
 	/* When not constructing vbases of abstract classes, at least mark
 	   the arguments expressions as read to avoid
 	   -Wunused-but-set-parameter false positives.  */
-	for (tree arg = arguments; arg; arg = TREE_CHAIN (arg))
-	  mark_exp_read (TREE_VALUE (arg));
+	cp_walk_tree (&arguments, mark_exp_read_r, NULL, NULL);
 
       if (inherited_base)
 	pop_deferring_access_checks ();

gcc/testsuite/ChangeLog

+2017-03-02  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/79782
+	* g++.dg/warn/Wunused-parm-10.C: New test.
+
 2017-03-02  Uros Bizjak  <ubizjak@gmail.com>
 
 	* gcc.dg/rtl/x86_64/*.c: Test for

gcc/testsuite/g++.dg/warn/Wunused-parm-10.C

+// PR c++/79782
+// { dg-do compile { target c++11 } }
+// { dg-options "-Wunused-but-set-parameter -Wunused-parameter" }
+
+struct E { virtual E *foo () const = 0; };
+struct F : virtual public E { };
+struct G : public virtual F { G (int x) : F () { } };				// { dg-warning "unused parameter" }
+struct H : virtual public E { H (int x, int y); };
+struct I : public virtual H { I (int x, int y) : H (x, y) { } };		// { dg-bogus "set but not used" }
+struct J : public virtual H { J (int x, int y) : H { x, y } { } };		// { dg-bogus "set but not used" }
+struct K : public virtual H { K (int x, int y) : H (x * 0, y + 1) { } };	// { dg-bogus "set but not used" }
+struct L : public virtual H { L (int x, int y) : H { x & 0, y | 1 } { } };	// { dg-bogus "set but not used" }