diff --git a/firmware/Makefile b/firmware/Makefile
index ccf58438..cc406738 100644
--- a/firmware/Makefile
+++ b/firmware/Makefile
@@ -164,14 +164,14 @@ CFLAGS += -Wno-suggest-attribute=noreturn
 # -mlong-calls  -Wall
 #CFLAGS += -save-temps -fverbose-asm
 #CFLAGS += -Wa,-a,-ad
-CFLAGS += -D__ARM
+CFLAGS += -D__ARM -fno-builtin
 CFLAGS += --param max-inline-insns-single=500 -mcpu=cortex-m3 -mthumb # -mfix-cortex-m3-ldrd
 CFLAGS += -ffunction-sections -g $(OPTIMIZATION) $(INCLUDES) -D$(CHIP) -DTRACE_LEVEL=$(TRACE_LEVEL) -DALLOW_PEER_ERASE=$(ALLOW_PEER_ERASE)
 CFLAGS += -DGIT_VERSION=\"$(GIT_VERSION)\"
 CFLAGS += -DBOARD=\"$(BOARD)\" -DBOARD_$(BOARD)
 CFLAGS += -DAPPLICATION=\"$(APP)\" -DAPPLICATION_$(APP)
 ASFLAGS = -mcpu=cortex-m3 -mthumb -Wall -g $(OPTIMIZATION) $(INCLUDES) -D$(CHIP) -D__ASSEMBLY__
-LDFLAGS = -mcpu=cortex-m3 -mthumb -Wl,--cref -Wl,--check-sections -Wl,--gc-sections -Wl,--entry=ResetException -Wl,--unresolved-symbols=report-all -Wl,--warn-common -Wl,--warn-section-align -Wl,--warn-unresolved-symbols -Wl,--print-memory-usage $(LIB)
+LDFLAGS = -mcpu=cortex-m3 -mthumb -Wl,--cref -Wl,--check-sections -Wl,--gc-sections -Wl,--entry=ResetException -Wl,--unresolved-symbols=report-all -Wl,--warn-common -Wl,--warn-section-align -Wl,--print-memory-usage -Wl,--no-undefined $(LIB)
 #LD_OPTIONAL=-Wl,--print-gc-sections -Wl,--stats
 
 # Append BIN directories to output filename
diff --git a/firmware/libboard/common/source/board_lowlevel.c b/firmware/libboard/common/source/board_lowlevel.c
index b4d7d32c..1ddbcba2 100644
--- a/firmware/libboard/common/source/board_lowlevel.c
+++ b/firmware/libboard/common/source/board_lowlevel.c
@@ -218,3 +218,8 @@ void mdelay(unsigned int msecs)
 	do {
 	} while ((jiffies - jiffies_start) < msecs);
 }
+
+void abort() {
+	NVIC_SystemReset();
+	while(1) {};
+}