diff --git a/include/ChangeLog b/include/ChangeLog
index 0dc6acd04..812e6fcde 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,7 @@
+2001-08-01  Aldy Hernandez  <aldyh@redhat.com>
+
+	* opcode/mips.h (INSN_ISA_MASK): Nuke bits 12-15.
+
 2001-07-18  Andreas Jaeger  <aj@suse.de>
 
 	* xregex2.h: Place under LGPL version 2.1.
diff --git a/include/opcode/mips.h b/include/opcode/mips.h
index 7fd4703e5..8fc11a31d 100644
--- a/include/opcode/mips.h
+++ b/include/opcode/mips.h
@@ -307,7 +307,7 @@ struct mips_opcode
    ORs of these bits, indicatingthat they support the instructions
    defined at the given level.  */
 
-#define INSN_ISA_MASK		  0x0000ffff
+#define INSN_ISA_MASK		  0x00000fff
 #define INSN_ISA1                 0x00000010
 #define INSN_ISA2                 0x00000020
 #define INSN_ISA3                 0x00000040