diff --git a/platformio.ini b/platformio.ini
index 580d270b7e0a0a2d92d81bd04366a37bc2345490..a49e25edb3fcc92598b127f68bf6e029062808a5 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -15,7 +15,7 @@ extends = fun_base
 ; for examples that use ch32v003fun as their base
 [fun_base]
 board_build.ldscript = ch32v003fun/ch32v003fun.ld
-build_flags = -flto -Ich32v003fun -I/usr/include/newlib -DTINYVECTOR -lgcc -Iextralibs -I.
+build_flags = -flto -Ich32v003fun -I/usr/include/newlib -lgcc -Iextralibs -I.
 build_src_filter = +<ch32v003fun>
 extra_libs_srcs = +<extralibs>