re PR rtl-optimization/68287 (conditional jump or move depends on uninitialized…

re PR rtl-optimization/68287 (conditional jump or move depends on uninitialized value in lra-lives.c:1048)

Fix PR rtl-optimization/68287

	PR rtl-optimization/68287
	* lra-lives.c (lra_create_live_ranges_1): Reserve the right
	number of elements.

Co-Authored-By: Richard Biener <rguenther@suse.de>

From-SVN: r230163

gcc/ChangeLog

+2015-11-11  Martin Liska  <mliska@suse.cz>
+	    Richard Biener  <rguenther@suse.de>
+
+	PR rtl-optimization/68287
+	* lra-lives.c (lra_create_live_ranges_1): Reserve the right
+	number of elements.
+
 2015-11-11  Simon Dardis  <simon.dardis@imgtec.com>
 
 	* config/mips/mips.c (mips_breakable_sequence_p): New function.

gcc/lra-lives.c

@@ -1241,8 +1241,8 @@ lra_create_live_ranges_1 (bool all_p, bool dead_insn_p)
   unused_set = sparseset_alloc (max_regno);
   curr_point = 0;
   unsigned new_length = get_max_uid () * 2;
-  if (point_freq_vec.length () < new_length)
-    point_freq_vec.safe_grow (new_length);
+  point_freq_vec.truncate (0);
+  point_freq_vec.reserve_exact (new_length);
   lra_point_freq = point_freq_vec.address ();
   int *post_order_rev_cfg = XNEWVEC (int, last_basic_block_for_fn (cfun));
   int n_blocks_inverted = inverted_post_order_compute (post_order_rev_cfg);