re PR debug/90914 (ICE in schedule_generic_params_dies_gen, at dwarf2out.c:27153)

2019-06-21  Richard Biener  <rguenther@suse.de>

	PR debug/90914
	* dwarf2out.c (prune_unused_types_walk): Always consider
	function-local extern declarations as used.

	* g++.dg/debug/pr90914.C: New testcase.

From-SVN: r272547

gcc/ChangeLog

 2019-06-21  Richard Biener  <rguenther@suse.de>
 
+	PR debug/90914
+	* dwarf2out.c (prune_unused_types_walk): Always consider
+	function-local extern declarations as used.
+
+2019-06-21  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/90913
 	* tree-vect-loop-manip.c (vect_loop_versioning): Do not re-use
 	the scalar variant of if-conversion versioning.

gcc/dwarf2out.c

@@ -29419,9 +29419,16 @@ prune_unused_types_walk (dw_die_ref die)
 	    break;
 
 	  /* premark_used_variables marks external variables --- don't mark
-	     them here.  */
+	     them here.  But function-local externals are always considered
+	     used.  */
 	  if (get_AT (die, DW_AT_external))
-	    return;
+	    {
+	      for (c = die->die_parent; c; c = c->die_parent)
+		if (c->die_tag == DW_TAG_subprogram)
+		  break;
+	      if (!c)
+		return;
+	    }
 	}
       /* FALLTHROUGH */
 

gcc/testsuite/ChangeLog

 2019-06-21  Richard Biener  <rguenther@suse.de>
 
+	PR debug/90914
+	* g++.dg/debug/pr90914.C: New testcase.
+
+2019-06-21  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/90913
 	* gfortran.dg/vect/pr90913.f90: New testcase.
 

gcc/testsuite/g++.dg/debug/pr90914.C

+// { dg-do compile }
+// { dg-additional-options "-feliminate-unused-debug-symbols" }
+
+template <class> class A;
+void f ()
+{
+  extern A <double> b;
+}