diff --git a/src/engine/jam.h b/src/engine/jam.h
index 984a4a41b..25e5736fd 100644
--- a/src/engine/jam.h
+++ b/src/engine/jam.h
@@ -412,9 +412,9 @@
 #endif
 
 #ifdef __mips__
-  #if defined(_ABI64)
+  #if _MIPS_SIM == _MIPS_SIM_ABI64
     #define OSPLAT "OSPLAT=MIPS64"
-  #elif defined(_ABIO32)
+  #elif _MIPS_SIM == _MIPS_SIM_ABI32
     #define OSPLAT "OSPLAT=MIPS32"
   #endif
 #endif