diff --git a/env_support/rt-thread/SConscript b/env_support/rt-thread/SConscript
index 567da0290..defae78ff 100644
--- a/env_support/rt-thread/SConscript
+++ b/env_support/rt-thread/SConscript
@@ -53,12 +53,10 @@ if GetDepend('PKG_USING_LVGL_DEMOS'):
                 inc = inc + [current_path]
 
 LOCAL_CFLAGS = ''
-if rtconfig.PLATFORM == 'gcc': # GCC
+if rtconfig.PLATFORM == 'gcc' or rtconfig.PLATFORM == 'armclang': # GCC or Keil AC6
     LOCAL_CFLAGS += ' -std=c99'
 elif rtconfig.PLATFORM == 'armcc': # Keil AC5
-    LOCAL_CFLAGS += ' --c99 --gnu -g -W'
-elif rtconfig.PLATFORM == 'armclang': # Keil AC6
-    LOCAL_CFLAGS += ' -std=c99 -g -w'
+    LOCAL_CFLAGS += ' --c99 --gnu'
 
 group = group + DefineGroup('LVGL', src, depend = ['PKG_USING_LVGL'], CPPPATH = inc, LOCAL_CFLAGS = LOCAL_CFLAGS)
 
diff --git a/src/misc/lv_types.h b/src/misc/lv_types.h
index 9f8ef4ca6..84aee1030 100644
--- a/src/misc/lv_types.h
+++ b/src/misc/lv_types.h
@@ -77,7 +77,7 @@ typedef uint32_t lv_uintptr_t;
 #define _LV_CONCAT3(x, y, z) x ## y ## z
 #define LV_CONCAT3(x, y, z) _LV_CONCAT3(x, y, z)
 
-#if defined(PYCPARSER)
+#if defined(PYCPARSER) || defined(__CC_ARM)
 #define LV_FORMAT_ATTRIBUTE(fmtstr, vararg)
 #elif defined(__GNUC__) && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 4) || __GNUC__ > 4)
 #define LV_FORMAT_ATTRIBUTE(fmtstr, vararg) __attribute__((format(gnu_printf, fmtstr, vararg)))