diff --git a/src/apple2.h b/src/apple2.h
index 81c9889c..c854c6a0 100644
--- a/src/apple2.h
+++ b/src/apple2.h
@@ -22,7 +22,7 @@
 #endif
 
 // Virtual machine is an Apple ][ (not an NES, etc...)
-#define __APPLE2_VM__ 1
+#define APPLE2_VM 1
 
 /* Symbol naming issues */
 #ifdef NO_UNDERSCORES
diff --git a/src/x86/cpu.S b/src/x86/cpu.S
index 15e7787d..00b65dea 100644
--- a/src/x86/cpu.S
+++ b/src/x86/cpu.S
@@ -2118,7 +2118,7 @@ E(cpu65_run)
                 movzbLQ SN(cpu65_current)+4, XY_Reg_X
                 movb    SN(cpu65_current)+5, Y_Reg
                 movb    SN(cpu65_current)+6, SP_Reg_L
-#ifdef __APPLE2_VM__
+#ifdef APPLE2_VM
                 // Apple //e machine specific set stack point to ALTZP (or not)
                 movLQ   SN(base_stackzp), _XAX
                 subLQ   $SN(apple_ii_64k), _XAX