I used this tutorial to setup all of my software: http://www.angstromsandalgorithms.com/free-eclipse-arm-gcc-openocd-toolchain-for-windows-part-3-eclipse-ide/
I'm using an STM32F405RGT6 arm. I'm also on windows. I have tried adding -lm everywhere in the makefile and havn't had anything work. Basically I just want to be able to #include "math.h" so I can use the math functions...I'm also assuming placing -lm in the right place is all I need to do from all the google searches I've done...I'm also thinking my makefile might be not be linking things correctly and/or i might not have things linked properly in eclipse.
Here is my makefile:
# Makefile for compiling the Getting Started project
#-------------------------------------------------------------------------------
# User-modifiable options
#-------------------------------------------------------------------------------
# Trace level used for compilation
# (can be overriden by adding TRACE_LEVEL=#number to the command-line)
# TRACE_LEVEL_DEBUG 5
# TRACE_LEVEL_INFO 4
# TRACE_LEVEL_WARNING 3
# TRACE_LEVEL_ERROR 2
# TRACE_LEVEL_FATAL 1
# TRACE_LEVEL_NO_TRACE 0
TRACE_LEVEL = 4
# Optimization level
OPTIMIZATION = -O0
# Output file basename
OUTPUT = main
# Output directories
BIN = .
OBJ = obj
# library dirs
LIBRARYSRC = ./lib/src
STARTUPFILE = ./lib/startup_stm32f4xx.s
#-------------------------------------------------------------------------------
# Tools
#-------------------------------------------------------------------------------
# Tool suffix when cross-compiling
CROSS_COMPILE = arm-none-eabi-
CC = $(CROSS_COMPILE)gcc
SIZE = $(CROSS_COMPILE)size
STRIP = $(CROSS_COMPILE)strip
OBJCOPY = $(CROSS_COMPILE)objcopy
OBJDUMP = $(CROSS_COMPILE)objdump
LD = $(CROSS_COMPILE)ld
AS = $(CROSS_COMPILE)as
#-------------------------------------------------------------------------------
# Files
#-------------------------------------------------------------------------------
# include folders
INCLUDES = -I./
INCLUDES += -I./lib/
INCLUDES += -I./lib/inc/
INCLUDES += -I./lib/inc/../../
# Objects built from C source files
C_OBJECTS = $(OBJ)/main.o
C_OBJECTS += $(OBJ)/system_stm32f4xx.o
C_OBJECTS += $(OBJ)/stm32f4xx_gpio.o
C_OBJECTS += $(OBJ)/stm32f4xx_rcc.o
C_OBJECTS += $(OBJ)/stm32f4xx_it.o
# Objects built from Assembly source files
ASM_OBJECTS = $(OBJ)/startup_stm32f4xx.o
LINKER_SCRIPT = ./lib/stm32f4xx_flash.ld
#LINKER_SCRIPT = ./lib/stm32f4xx_flash_extsram.ld
# Append OBJ and BIN directories to output filename
OUTPUT := $(BIN)/$(OUTPUT)
#-------------------------------------------------------------------------------
# Rules
#-------------------------------------------------------------------------------
# Flags
CFLAGS = -Wall -fno-common -c -g -mcpu=cortex-m3 -mthumb
CFLAGS += -g $(OPTIMIZATION) $(INCLUDES) -DTRACE_LEVEL=$(TRACE_LEVEL)
ASFLAGS = -g -mapcs-32
LDFLAGS = -g -v -nostartfiles
OBJCOPYFLAGS = -O binary
OBJDUMPFLAGS = -x --syms -S
all: $(BIN) $(OBJ) $(OUTPUT).out
$(BIN) $(OBJ):
mkdir $@
$(OUTPUT).out: $(C_OBJECTS) $(ASM_OBJECTS) $(LINKER_SCRIPT)
@ echo "..linking"
$(LD) $(LDFLAGS) -Map $(OUTPUT).map -T$(LINKER_SCRIPT) -o $(OUTPUT).out $(C_OBJECTS) $(ASM_OBJECTS) libgcc.a
$(OBJCOPY) $(OBJCOPYFLAGS) $(OUTPUT).out $(OUTPUT).bin
# $(OBJDUMP) $(OBJDUMPFLAGS) $(OUTPUT).out > $(OUTPUT).lss
@ echo "...completed."
$(C_OBJECTS): main.c system_stm32f4xx.c
@ echo ".compiling"
$(CC) $(CFLAGS) -o $(OBJ)/main.o main.c
$(CC) $(CFLAGS) -o $(OBJ)/system_stm32f4xx.o system_stm32f4xx.c
$(CC) $(CFLAGS) -o $(OBJ)/stm32f4xx_it.o stm32f4xx_it.c
@ echo ".compiling libraries"
$(CC) $(CFLAGS) -o $(OBJ)/stm32f4xx_gpio.o $(LIBRARYSRC)/stm32f4xx_gpio.c
$(CC) $(CFLAGS) -o $(OBJ)/stm32f4xx_rcc.o $(LIBRARYSRC)/stm32f4xx_rcc.c
$(ASM_OBJECTS): $(STARTUPFILE)
@ echo ".assembling"
$(AS) $(ASFLAGS) -o $(OBJ)/startup_stm32f4xx.o $(STARTUPFILE)
clean:
-rm -f $(OBJ)/*.o $(BIN)/*.out $(BIN)/*.bin $(BIN)/*.dmp $(BIN)/*.map $(BIN)/*.lss
