diff --git a/utils/CMakeLists.txt b/utils/CMakeLists.txt
index 7b88397d..8ef3c884 100644
--- a/utils/CMakeLists.txt
+++ b/utils/CMakeLists.txt
@@ -53,14 +53,12 @@ if(CONFIG_VLIBC)
         sdk_add_compile_definitions(-DCONFIG_VLIBC_FATFS)
     endif()
 
-    # sdk_add_compile_definitions(-Dprintf=vlibc_printf)
     sdk_library_add_sources(vlibc/printf.c)
     sdk_library_add_sources(vlibc/syscalls.c)
     sdk_library_add_sources(vlibc/vlibc_stdio.c)
     sdk_library_add_sources(vlibc/vlibc_vsnprintf.c)
     sdk_add_include_directories(vlibc)
 else()
-    # sdk_add_compile_definitions(-Dprintf=bflb_printf)
     sdk_library_add_sources(libc/vsnprintf.c)
     sdk_library_add_sources(libc/syscalls.c)
     sdk_library_add_sources(libc/printf.c)
diff --git a/utils/libc/printf.c b/utils/libc/printf.c
index df8010b2..f1a0d180 100644
--- a/utils/libc/printf.c
+++ b/utils/libc/printf.c
@@ -3,19 +3,10 @@
 
 struct bflb_device_s *console = NULL;
 
-#ifdef CONFIG_CUSTOM_PRINTF
-int puts(const char *s)
-{
-    int len = strlen(s);
+int puts(const char *fmt) __attribute__((alias("bflb_printf")));
+int printf(const char *fmt, ...) __attribute__((alias("bflb_printf")));
 
-    bflb_uart_put(console, (uint8_t *)s, len);
-    if (s[len - 1] == '\r') {
-        bflb_uart_putchar(console, '\n');
-    }
-    return len;
-}
-
-int printf(const char *fmt, ...)
+int bflb_printf(const char *fmt, ...)
 {
     char print_buf[128];
     uint32_t len;
@@ -31,7 +22,6 @@ int printf(const char *fmt, ...)
 
     return 0;
 }
-#endif
 
 #define __is_print(ch) ((unsigned int)((ch) - ' ') < 127u - ' ')
 void bflb_dump_hex(const void *ptr, uint32_t buflen)
diff --git a/utils/libc/syscalls.c b/utils/libc/syscalls.c
index 825ca37d..036c25e3 100644
--- a/utils/libc/syscalls.c
+++ b/utils/libc/syscalls.c
@@ -10,7 +10,7 @@ extern struct bflb_device_s *console;
 
 /* Reentrant versions of system calls.  */
 
-/* global errno in RT-Thread */
+/* global errno */
 static volatile int _sys_errno = 0;
 
 #ifndef _REENT_ONLY