diff --git a/bsp/mm32l3xx/Libraries/SConscript b/bsp/mm32l3xx/Libraries/SConscript
index 91b6d144b3..14e95cd282 100644
--- a/bsp/mm32l3xx/Libraries/SConscript
+++ b/bsp/mm32l3xx/Libraries/SConscript
@@ -7,9 +7,7 @@ CPPPATH = [cwd + '/CMSIS/KEIL_CORE', cwd + '/MM32L3xx/Include',  cwd + '/MM32L3x
 src += Glob('MM32L3xx/HAL_lib/src/*.c')
 CPPDEFINES = ['USE_STDPERIPH_DRIVER']
 
-if rtconfig.CROSS_TOOL == 'gcc':
-    src += ['MM32L3xx/Source/GCC_StartAsm/startup_MM32L3xx.s']
-elif rtconfig.CROSS_TOOL == 'keil':
+if rtconfig.CROSS_TOOL == 'keil':
     src += ['MM32L3xx/Source/KEIL_StartAsm/startup_MM32L3xx.s']
 elif rtconfig.CROSS_TOOL == 'iar':
     src += ['MM32L3xx/Source/IAR_StartAsm/startup_MM32L3xx.s']
diff --git a/bsp/mm32l3xx/rtconfig.py b/bsp/mm32l3xx/rtconfig.py
index 241b1456fa..1e87cf72e0 100644
--- a/bsp/mm32l3xx/rtconfig.py
+++ b/bsp/mm32l3xx/rtconfig.py
@@ -42,7 +42,7 @@ if PLATFORM == 'gcc':
     OBJDUMP = PREFIX + 'objdump'
     OBJCPY = PREFIX + 'objcopy'
 
-    DEVICE = ' -mcpu=' + CPU + ' -ffunction-sections -fdata-sections -Wall'
+    DEVICE = ' -mcpu=cortex-m3 -mthumb -ffunction-sections -fdata-sections -Wall'
     CFLAGS = DEVICE + ' -std=c99'
     AFLAGS = ' -c' + DEVICE + ' -x assembler-with-cpp -Wa,-mimplicit-it=thumb '
     LFLAGS = DEVICE + ' -Wl,--gc-sections,-Map=rtthread.map,-cref,-u,Reset_Handler -T drivers/linker_scripts/link.lds'