[COMMITTED PATCH] dwarf2read.c (setup_type_unit_groups): Add comment.

[Doug Evans]

Hi.

There are some things I'd like to clean up here, but a proper job
requires more time than I have right now.
This comment at least clears something up for me having not read
the code in awhile.

2015-09-30  Doug Evans  <dje@google.com>

	* dwarf2read.c (setup_type_unit_groups): Add comment.

diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 5b12342..ddd4a4c 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -9332,6 +9332,11 @@ setup_type_unit_groups (struct die_info *die, struct  
dwarf2_cu *cu)
      {
        struct compunit_symtab *cust = dwarf2_start_symtab (cu, "", NULL, 0);

+      /* Note: We don't assign tu_group->compunit_symtab yet because we're
+	 still initializing it, and our caller (a few levels up)
+	 process_full_type_unit still needs to know if this is the first
+	 time.  */
+
        tu_group->num_symtabs = lh->num_file_names;
        tu_group->symtabs = XNEWVEC (struct symtab *, lh->num_file_names);