re PR rtl-optimization/85302 (ICE in size_of_loc_descr, at dwarf2out.c:1771 on i686-linux-gnu)

	PR debug/85302
	* dwarf2out.c (skip_loc_list_entry): Don't call size_of_locs if
	SIZEP is NULL.
	(output_loc_list): Pass address of a dummy size variable even in the
	locview handling loop.
	(index_location_lists): Add comment on why skip_loc_list_entry can't
	call size_of_locs.

	* g++.dg/debug/dwarf2/pr85302.C: New test.

From-SVN: r259311

4 files changed, 47 insertions, 6 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9e1d6f8..ed58fc2 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+2018-04-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/85302
+	* dwarf2out.c (skip_loc_list_entry): Don't call size_of_locs if
+	SIZEP is NULL.
+	(output_loc_list): Pass address of a dummy size variable even in the
+	locview handling loop.
+	(index_location_lists): Add comment on why skip_loc_list_entry can't
+	call size_of_locs.
+
 2018-04-11  Thomas Preud'homme  <thomas.preudhomme@arm.com>
 
 	PR target/85261
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 50a41c5..0838ebf 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -10032,18 +10032,22 @@ maybe_gen_llsym (dw_loc_list_ref list)
   gen_llsym (list);
 }
 
-/* Determine whether or not to skip loc_list entry CURR.  If we're not
+/* Determine whether or not to skip loc_list entry CURR.  If SIZEP is
+   NULL, don't consider size of the location expression.  If we're not
    to skip it, and SIZEP is non-null, store the size of CURR->expr's
    representation in *SIZEP.  */
 
 static bool
-skip_loc_list_entry (dw_loc_list_ref curr, unsigned long *sizep = 0)
+skip_loc_list_entry (dw_loc_list_ref curr, unsigned long *sizep = NULL)
 {
   /* Don't output an entry that starts and ends at the same address.  */
   if (strcmp (curr->begin, curr->end) == 0
       && curr->vbegin == curr->vend && !curr->force)
     return true;
 
+  if (!sizep)
+    return false;
+
   unsigned long size = size_of_locs (curr->expr);
 
   /* If the expression is too large, drop it on the floor.  We could
@@ -10053,8 +10057,7 @@ skip_loc_list_entry (dw_loc_list_ref curr, unsigned long *sizep = 0)
   if (dwarf_version < 5 && size > 0xffff)
     return true;
 
-  if (sizep)
-    *sizep = size;
+  *sizep = size;
 
   return false;
 }
@@ -10121,7 +10124,9 @@ output_loc_list (dw_loc_list_ref list_head)
       for (dw_loc_list_ref curr = list_head; curr != NULL;
 	   curr = curr->dw_loc_next)
 	{
-	  if (skip_loc_list_entry (curr))
+	  unsigned long size;
+
+	  if (skip_loc_list_entry (curr, &size))
 	    continue;
 
 	  vcount++;
@@ -30887,7 +30892,14 @@ index_location_lists (dw_die_ref die)
         for (curr = list; curr != NULL; curr = curr->dw_loc_next)
           {
             /* Don't index an entry that has already been indexed
-               or won't be output.  */
+	       or won't be output.  Make sure skip_loc_list_entry doesn't
+	       call size_of_locs, because that might cause circular dependency,
+	       index_location_lists requiring address table indexes to be
+	       computed, but adding new indexes through add_addr_table_entry
+	       and address table index computation requiring no new additions
+	       to the hash table.  In the rare case of DWARF[234] >= 64KB
+	       location expression, we'll just waste unused address table entry
+	       for it.  */
             if (curr->begin_entry != NULL
                 || skip_loc_list_entry (curr))
               continue;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9b224f5..9f8b16a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-04-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/85302
+	* g++.dg/debug/dwarf2/pr85302.C: New test.
+
 2018-04-11  Thomas Preud'homme  <thomas.preudhomme@arm.com>
 
 	PR target/85261
diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/pr85302.C b/gcc/testsuite/g++.dg/debug/dwarf2/pr85302.C
new file mode 100644
index 0000000..97ac302
--- /dev/null
+++ b/gcc/testsuite/g++.dg/debug/dwarf2/pr85302.C
@@ -0,0 +1,14 @@
+// PR debug/85302
+// { dg-do compile }
+// { dg-options "-std=c++11 -gsplit-dwarf -O1" }
+// { dg-additional-options "-fPIE" { target pie } }
+
+struct A { const char *b; A (const char *c) : b(c) {} };
+struct B { void foo (A); };
+B e;
+
+void
+bar ()
+{
+  e.foo ("");
+}