diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index 52ebe868cc..514466ed63 100644
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,3 +1,7 @@
+2020-01-04  Alan Modra  <amodra@gmail.com>
+
+	* crx-dis.c (match_opcode): Avoid shift left of signed value.
+
 2020-01-04  Alan Modra  <amodra@gmail.com>
 
 	* d30v-dis.c (print_insn): Avoid signed overflow in left shift.
diff --git a/opcodes/crx-dis.c b/opcodes/crx-dis.c
index 18b6c6d9e6..011cd682fc 100644
--- a/opcodes/crx-dis.c
+++ b/opcodes/crx-dis.c
@@ -337,7 +337,7 @@ match_opcode (void)
   unsigned int mask;
 
   /* The instruction 'constant' opcode doewsn't exceed 32 bits.  */
-  unsigned int doubleWord = (words[1] + (words[0] << 16)) & 0xffffffff;
+  unsigned int doubleWord = words[1] + ((unsigned) words[0] << 16);
 
   /* Start searching from end of instruction table.  */
   instruction = &crx_instruction[NUMOPCODES - 2];