diff --git a/configs/qemu-i486/nsh/Make.defs b/configs/qemu-i486/nsh/Make.defs
index 7f5be321fd..0d16a608b0 100644
--- a/configs/qemu-i486/nsh/Make.defs
+++ b/configs/qemu-i486/nsh/Make.defs
@@ -71,7 +71,7 @@ ARCHDEFINES =
 
 # Check if building a 32-bit target with a 64-bit toolchain
 
-ifeq ($(ARCH_X86_M32),y)
+ifeq ($(CONFIG_ARCH_X86_M32),y)
 ARCHCPUFLAGS += -m32
 endif
 
diff --git a/configs/qemu-i486/ostest/Make.defs b/configs/qemu-i486/ostest/Make.defs
index 72f26452bb..e2ac40b09f 100644
--- a/configs/qemu-i486/ostest/Make.defs
+++ b/configs/qemu-i486/ostest/Make.defs
@@ -71,7 +71,7 @@ ARCHDEFINES =
 
 # Check if building a 32-bit target with a 64-bit toolchain
 
-ifeq ($(ARCH_X86_M32),y)
+ifeq ($(CONFIG_ARCH_X86_M32),y)
 ARCHCPUFLAGS += -m32
 endif
 
diff --git a/drivers/serial/uart_16550.c b/drivers/serial/uart_16550.c
index 022adf3abe..b55597bdf1 100644
--- a/drivers/serial/uart_16550.c
+++ b/drivers/serial/uart_16550.c
@@ -871,14 +871,17 @@ static int u16550_ioctl(struct file *filep, int cmd, unsigned long arg)
   struct inode      *inode = filep->f_inode;
   struct uart_dev_s *dev   = inode->i_private;
   struct u16550_s   *priv  = (FAR struct u16550_s *)dev->priv;
+  int ret;
 
 #ifdef CONFIG_SERIAL_UART_ARCH_IOCTL
-  int ret = uart_ioctl(filep, cmd, arg);
+  ret = uart_ioctl(filep, cmd, arg);
 
   if (ret != -ENOTTY)
     {
       return ret;
     }
+#else
+  ret = OK;
 #endif
 
   switch (cmd)