diff --git a/arm-asm.c b/arm-asm.c
index f672301c..fd6275aa 100644
--- a/arm-asm.c
+++ b/arm-asm.c
@@ -77,6 +77,8 @@ static void parse_operand(TCCState *s1, Operand *op)
             } else
                 next(); // skip register name
 
+            if ((1 << reg) < regset)
+                tcc_warning("registers will be processed in ascending order by hardware--but are not specified in ascending order here");
             regset |= 1 << reg;
             if (tok != ',')
                 break;