diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index ee4c9d8b21..296d187f24 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,9 @@
+2017-06-13  Andreas Arnez  <arnez@linux.vnet.ibm.com>
+
+	* dwarf2loc.c (write_pieced_value): In DWARF_VALUE_MEMORY,
+	truncate full bytes from dest_offset_bits before using it as an
+	offset into the buffer.
+
 2017-06-13  Andreas Arnez  <arnez@linux.vnet.ibm.com>
 
 	* dwarf2loc.c (write_pieced_value): Include transfer size in
diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c
index 2849dadb77..67a123fd42 100644
--- a/gdb/dwarf2loc.c
+++ b/gdb/dwarf2loc.c
@@ -2058,7 +2058,7 @@ write_pieced_value (struct value *to, struct value *from)
 	      read_memory (p->v.mem.addr + dest_offset, buffer.data (), 1);
 	      read_memory (p->v.mem.addr + dest_offset + this_size - 1,
 			   &buffer[this_size - 1], 1);
-	      copy_bitwise (buffer.data (), dest_offset_bits,
+	      copy_bitwise (buffer.data (), dest_offset_bits % 8,
 			    contents, source_offset_bits,
 			    this_size_bits,
 			    bits_big_endian);