diff --git a/libsrc/rp6502/codepage.c b/libsrc/rp6502/codepage.c
index e28726f04f..64222ff9b9 100644
--- a/libsrc/rp6502/codepage.c
+++ b/libsrc/rp6502/codepage.c
@@ -1,6 +1,6 @@
 #include <rp6502.h>
 
-int __fastcall__ codepage (void)
+int codepage (void)
 {
     return ria_call_int (RIA_OP_CODEPAGE);
 }
diff --git a/libsrc/rp6502/lrand.c b/libsrc/rp6502/lrand.c
index 6434425df0..61175e5829 100644
--- a/libsrc/rp6502/lrand.c
+++ b/libsrc/rp6502/lrand.c
@@ -1,6 +1,6 @@
 #include <rp6502.h>
 
-long __fastcall__ lrand (void)
+long lrand (void)
 {
     return ria_call_long (RIA_OP_LRAND);
 }
diff --git a/libsrc/rp6502/phi2.c b/libsrc/rp6502/phi2.c
index 1275e256ef..8cf59f1f31 100644
--- a/libsrc/rp6502/phi2.c
+++ b/libsrc/rp6502/phi2.c
@@ -1,6 +1,6 @@
 #include <rp6502.h>
 
-int __fastcall__ phi2 (void)
+int phi2 (void)
 {
     return ria_call_int (RIA_OP_PHI2);
 }
diff --git a/libsrc/rp6502/ria.s b/libsrc/rp6502/ria.s
index a1b53efb1b..53ec74e157 100644
--- a/libsrc/rp6502/ria.s
+++ b/libsrc/rp6502/ria.s
@@ -28,7 +28,7 @@ _ria_push_int:
     sta RIA_XSTACK
     rts
 
-; long __fastcall__ ria_pop_long(void);
+; long ria_pop_long(void);
 _ria_pop_long:
     jsr _ria_pop_int
     ldy RIA_XSTACK
@@ -37,7 +37,7 @@ _ria_pop_long:
     sty sreg+1
     rts
 
-; int __fastcall__ ria_pop_int(void);
+; int ria_pop_int(void);
 _ria_pop_int:
     lda RIA_XSTACK
     ldx RIA_XSTACK