diff --git a/Core/z80_cpu.c b/Core/z80_cpu.c
index e187c3e..705fefe 100644
--- a/Core/z80_cpu.c
+++ b/Core/z80_cpu.c
@@ -338,7 +338,7 @@ static void add_hl_rr(GB_gameboy_t *gb, uint8_t opcode)
         gb->registers[GB_REGISTER_AF] |= GB_HALF_CARRY_FLAG;
     }
 
-    if ( ((unsigned long) hl) + ((unsigned long) rr) & 0x10000) {
+    if ( ((unsigned long) hl) + (((unsigned long) rr) & 0x10000)) {
         gb->registers[GB_REGISTER_AF] |= GB_CARRY_FLAG;
     }
 }