re PR tree-optimization/86850 (ubsan: runtime error: member call on null pointer)

2018-11-06  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/86850
	* vec.h (vec<T, va_heap, vl_ptr>::splice): Check src.length ()
	instead of src.m_vec.

From-SVN: r265848

gcc/ChangeLog

+2018-11-06  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/86850
+	* vec.h (vec<T, va_heap, vl_ptr>::splice): Check src.length ()
+	instead of src.m_vec.
+ 
 2018-11-06  Jan Hubicka  <jh@suse.cz>
 
 	* tree.c (fld_simplified_type_name): Break out form ...

gcc/vec.h

@@ -1688,7 +1688,7 @@ template<typename T>
 inline void
 vec<T, va_heap, vl_ptr>::splice (const vec<T, va_heap, vl_ptr> &src)
 {
-  if (src.m_vec)
+  if (src.length ())
     m_vec->splice (*(src.m_vec));
 }