re PR middle-end/69915 (ICE: SIGSEGV with -O -ftracer with broken backtrace)

	PR middle-end/69915
	* tree.c (build_vector_from_ctor): Fix handling of VECTOR_CST
	elements.

	* gcc.dg/pr69915.c: New test.

From-SVN: r233664

gcc/ChangeLog

+2016-02-24  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/69915
+	* tree.c (build_vector_from_ctor): Fix handling of VECTOR_CST
+	elements.
+
 2016-02-24  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	PR rtl-optimization/69886

gcc/testsuite/ChangeLog

+2016-02-24  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/69915
+	* gcc.dg/pr69915.c: New test.
+
 2016-02-24  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	PR rtl-optimization/69886

gcc/testsuite/gcc.dg/pr69915.c

+/* PR middle-end/69915 */
+/* { dg-do compile } */
+/* { dg-options "-O -ftracer" } */
+
+typedef unsigned short V __attribute__ ((vector_size (32)));
+
+unsigned
+foo (unsigned x, unsigned c, V *p)
+{
+  V v = *p;
+  if (c < 360)
+    v = (V) { 0 };
+  v *= (V) { x };
+  return v[1];
+}

gcc/tree.c

@@ -1749,7 +1749,7 @@ build_vector_from_ctor (tree type, vec<constructor_elt, va_gc> *v)
       else
 	vec[pos++] = value;
     }
-  for (; idx < TYPE_VECTOR_SUBPARTS (type); ++idx)
+  while (pos < TYPE_VECTOR_SUBPARTS (type))
     vec[pos++] = build_zero_cst (TREE_TYPE (type));
 
   return build_vector (type, vec);