[C++ PATCH] Fix ICE in build_ctor_subob_ref during replace_placeholders (PR c++/92524, take 2)

[Jakub Jelinek]

On Tue, Nov 26, 2019 at 04:58:01PM -0500, Jason Merrill wrote:
> Hmm, we shouldn't have any PLACEHOLDER_EXPR under a RANGE_EXPR; if we did,
> any references to its address would end up all referring to the first
> element of the range, which would be wrong.  How about skipping RANGE_EXPR
> in replace_placeholders_r?

So like this?
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2019-11-27  Jakub Jelinek  <ja...@redhat.com>

        PR c++/92524
        * tree.c (replace_placeholders_r): Don't walk constructor elts with
        RANGE_EXPR indexes.

        * g++.dg/cpp0x/pr92524.C: New test.

--- gcc/cp/tree.c.jj    2019-11-26 23:09:55.904101392 +0100
+++ gcc/cp/tree.c       2019-11-26 23:13:14.308070759 +0100
@@ -3144,6 +3144,11 @@ replace_placeholders_r (tree* t, int* wa
            tree type = TREE_TYPE (*valp);
            tree subob = obj;
 
+           /* Elements with RANGE_EXPR index shouldn't have any
+              placeholders in them.  */
+           if (ce->index && TREE_CODE (ce->index) == RANGE_EXPR)
+             continue;
+
            if (TREE_CODE (*valp) == CONSTRUCTOR
                && AGGREGATE_TYPE_P (type))
              {
--- gcc/testsuite/g++.dg/cpp0x/pr92524.C.jj     2019-11-26 23:09:46.810240310 
+0100
+++ gcc/testsuite/g++.dg/cpp0x/pr92524.C        2019-11-26 23:09:46.810240310 
+0100
@@ -0,0 +1,12 @@
+// PR c++/92524
+// { dg-do compile { target c++11 } }
+
+struct A { char a = '*'; };
+struct B { A b[64]; };
+
+void
+foo ()
+{
+  A a;
+  B{a};
+}

        Jakub