[11u] RFR 8259710: Inlining trace leaks memory

[Roland Westrelin]

Original bug:
  https://bugs.openjdk.java.net/browse/JDK-8259710
  https://github.com/openjdk/jdk/commit/ca20c63c
 
The patch doesn't apply cleanly. Failed hunk is below but patch is
otherwise largely unchanged.

11u webrev:
  https://cr.openjdk.java.net/~roland/8259710.11u/webrev.00/
 
Testing: x86_64 build, executing non trivial app with -XX:+PrintInlining
 
Roland.

--- compile.cpp
+++ compile.cpp
@@ -4209,32 +4204,32 @@ void Compile::print_inlining_commit() {
   assert(print_inlining() || print_intrinsics(), "PrintInlining off?");
   // Transfer the message from _print_inlining_stream to the current
   // _print_inlining_list buffer and clear _print_inlining_stream.
-  _print_inlining_list->at(_print_inlining_idx).ss()->write(_print_inlining_stream->base(), _print_inlining_stream->size());
+  _print_inlining_list->at(_print_inlining_idx)->ss()->write(_print_inlining_stream->base(), _print_inlining_stream->size());
   print_inlining_reset();
 }
 
 void Compile::print_inlining_push() {
   // Add new buffer to the _print_inlining_list at current position
   _print_inlining_idx++;
-  _print_inlining_list->insert_before(_print_inlining_idx, PrintInliningBuffer());
+  _print_inlining_list->insert_before(_print_inlining_idx, new PrintInliningBuffer());
 }
 
-Compile::PrintInliningBuffer& Compile::print_inlining_current() {
+Compile::PrintInliningBuffer* Compile::print_inlining_current() {
   return _print_inlining_list->at(_print_inlining_idx);
 }
 
 void Compile::print_inlining_update(CallGenerator* cg) {
   if (print_inlining() || print_intrinsics()) {
     if (cg->is_late_inline()) {
-      if (print_inlining_current().cg() != cg &&
-          (print_inlining_current().cg() != NULL ||
-           print_inlining_current().ss()->size() != 0)) {
+      if (print_inlining_current()->cg() != cg &&
+          (print_inlining_current()->cg() != NULL ||
+           print_inlining_current()->ss()->size() != 0)) {
         print_inlining_push();
       }
       print_inlining_commit();
-      print_inlining_current().set_cg(cg);
+      print_inlining_current()->set_cg(cg);
     } else {
-      if (print_inlining_current().cg() != NULL) {
+      if (print_inlining_current()->cg() != NULL) {
         print_inlining_push();
       }
       print_inlining_commit();