diff --git a/minimal/Makefile b/minimal/Makefile
index 42c2d53127902abaea94cf04eabc9f7a38237bfa..3b446beae7a2086c24bb0647abca8c1710d76204 100644
--- a/minimal/Makefile
+++ b/minimal/Makefile
@@ -22,9 +22,9 @@ ifeq ($(CROSS), 1)
 DFU = ../tools/dfu.py
 PYDFU = ../tools/pydfu.py
 CFLAGS_CORTEX_M4 = -mthumb -mtune=cortex-m4 -mabi=aapcs-linux -mcpu=cortex-m4 -mfpu=fpv4-sp-d16 -mfloat-abi=hard -fsingle-precision-constant -Wdouble-promotion
-CFLAGS = $(INC) -Wall -Werror -std=gnu99 -nostdlib $(CFLAGS_CORTEX_M4) $(COPT)
+CFLAGS = $(INC) -Wall -Werror -std=c99 -nostdlib $(CFLAGS_CORTEX_M4) $(COPT)
 else
-CFLAGS = -m32 $(INC) -Wall -Werror -std=gnu99 $(COPT)
+CFLAGS = -m32 $(INC) -Wall -Werror -std=c99 $(COPT)
 endif
 
 #Debugging/Optimization
diff --git a/minimal/main.c b/minimal/main.c
index 496d925e774ad3b3b1ae49c4c262e9cfc89428b4..5cc88ff6687c6c8645bb1b9064062fa570c78338 100644
--- a/minimal/main.c
+++ b/minimal/main.c
@@ -106,7 +106,7 @@ extern uint32_t _estack, _sidata, _sdata, _edata, _sbss, _ebss;
 void Reset_Handler(void) __attribute__((naked));
 void Reset_Handler(void) {
     // set stack pointer
-    asm volatile ("ldr sp, =_estack");
+    __asm volatile ("ldr sp, =_estack");
     // copy .data section from flash to RAM
     for (uint32_t *src = &_sidata, *dest = &_sdata; dest < &_edata;) {
         *dest++ = *src++;