使用avr-g++/gcc配置项目报错：无法识别‘--out-implib’选项

问题场景 #

执行以下CMake配置命令：

cmake -B../build_atmega328 -S. -G Ninja -D CMAKE_C_COMPILER=C:\arduino\tools\avr-gcc\7.3.0-atmel3.6.1-arduino7\bin\avr-gcc.exe -D CMAKE_CXX_COMPILER=C:\arduino\tools\avr-gcc\7.3.0-atmel3.6.1-arduino7\bin\avr-g++.exe

出现链接器错误，核心提示：

c:/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/../lib/gcc/avr/7.3.0/../../../../avr/bin/ld.exe: unrecognized option '--out-implib'

导致C++编译器检测失败，完整错误输出如下：

E:\MyProject\display\display_controller>cmake -B../build_atmega328 -S. -G Ninja -D CMAKE_C_COMPILER=C:\arduino\tools\avr-gcc\7.3.0-atmel3.6.1-arduino7\bin\avr-gcc.exe -D CMAKE_CXX_COMPILER=C:\arduino\tools\avr-gcc\7.3.0-atmel3.6.1-arduino7\bin\avr-g++.exe
-- The CXX compiler identification is GNU 7.3.0
-- The C compiler identification is GNU 7.3.0
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - failed
-- Check for working CXX compiler: C:/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-g++.exe
-- Check for working CXX compiler: C:/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-g++.exe - broken
CMake Error at C:/Program Files/CMake/share/cmake-3.31/Modules/CMakeTestCXXCompiler.cmake:73 (message):
  The C++ compiler

    "C:/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-g++.exe"

  is not able to compile a simple test program.

  It fails with the following output:

    Change Dir: 'E:/MyProject/display/build_atmega328/CMakeFiles/CMakeScratch/TryCompile-njpofd'

    Run Build Command(s): E:/ninja/ninja.exe -v cmTC_3ce41
    [1/2] C:\arduino\tools\avr-gcc\7.3.0-atmel3.6.1-arduino7\bin\avr-g++.exe    -o CMakeFiles/cmTC_3ce41.dir/testCXXCompiler.cxx.obj -c E:/MyProject/display/build_atmega328/CMakeFiles/CMakeScratch/TryCompile-njpofd/testCXXCompiler.cxx
    [2/2] C:\Windows\system32\cmd.exe /C "cd . && C:\arduino\tools\avr-gcc\7.3.0-atmel3.6.1-arduino7\bin\avr-g++.exe   CMakeFiles/cmTC_3ce41.dir/testCXXCompiler.cxx.obj -o cmTC_3ce41.exe -Wl,--out-implib,libcmTC_3ce41.dll.a -Wl,--major-image-version,0,--minor-image-version,0  -lkernel32 -luser32 -lgdi32 -lwinspool -lshell32 -lole32 -loleaut32 -luuid -lcomdlg32 -ladvapi32 && cd ."
    FAILED: cmTC_3ce41.exe
    C:\Windows\system32\cmd.exe /C "cd . && C:\arduino\tools\avr-gcc\7.3.0-atmel3.6.1-arduino7\bin\avr-g++.exe   CMakeFiles/cmTC_3ce41.dir/testCXXCompiler.cxx.obj -o cmTC_3ce41.exe -Wl,--out-implib,libcmTC_3ce41.dll.a -Wl,--major-image-version,0,--minor-image-version,0  -lkernel32 -luser32 -lgdi32 -lwinspool -lshell32 -lole32 -loleaut32 -luuid -lcomdlg32 -ladvapi32 && cd ."
    c:/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/../lib/gcc/avr/7.3.0/../../../../avr/bin/ld.exe: unrecognized option '--out-implib'
    c:/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/../lib/gcc/avr/7.3.0/../../../../avr/bin/ld.exe: use the --help option for usage information
    collect2.exe: error: ld returned 1 exit status
    ninja: build stopped: subcommand failed.

错误原因 #

CMake默认认为是编译主机（Windows）平台的程序，自动添加了Windows特有的链接选项（--out-implib用于生成导入库，-lkernel32等Windows系统库），但AVR GCC是交叉编译工具链，其链接器avr-ld不支持这些Windows平台选项，因此报错。

解决方案 #

修改CMakeLists.txt，明确告诉CMake这是交叉编译，不要添加主机平台的链接选项：

1. 在cmake_minimum_required之后、project之前，添加交叉编译配置：

# 声明交叉编译模式
set(CMAKE_CROSSCOMPILING ON)
# 设置目标系统为无OS的嵌入式平台
set(CMAKE_SYSTEM_NAME Generic)
# 指定目标架构为AVR
set(CMAKE_SYSTEM_PROCESSOR avr)
# 强制跳过编译器ABI检测（交叉编译时ABI检测通常无效）
set(CMAKE_CXX_COMPILER_FORCED ON)
set(CMAKE_C_COMPILER_FORCED ON)

修改后的完整CMakeLists.txt如下：

# I target a recent cmake, it shouldn't be a problem on a dev machine
cmake_minimum_required(VERSION 3.11)

# 交叉编译配置
set(CMAKE_CROSSCOMPILING ON)
set(CMAKE_SYSTEM_NAME Generic)
set(CMAKE_SYSTEM_PROCESSOR avr)
set(CMAKE_CXX_COMPILER_FORCED ON)
set(CMAKE_C_COMPILER_FORCED ON)

# Project name
project("ConnectionsDisplay" VERSION 0.1 LANGUAGES CXX C)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
# Product filename
set(PRODUCT_NAME connections_display)

## AVR Chip Configuration
# 8Mhz, this should match the crystal on your board,
# I use 8Mhz and 3.3V for the lowest power consumption
set(F_CPU 8000000UL)
# CPU, you can find the list here:
# https://gcc.gnu.org/onlinedocs/gcc/AVR-Options.html
set(MCU atmega328p)
# Default Baudrate for UART, read avr include/util/setbaud.h for usage
set(BAUD 9600)
# The programmer to use, read avrdude manual for list
set(PROG_TYPE avrispmkII)

# AVR Fuses, must be in concordance with your hardware and F_CPU
# http://eleccelerator.com/fusecalc/fusecalc.php?chip=atmega328p
set(E_FUSE 0xfd)
set(H_FUSE 0xda)
set(L_FUSE 0xfd)
set(LOCK_BIT 0xff)

set(CMAKE_AVR_TOOL_COMPILERS "C:\\arduino\\tools\\avr-gcc\\7.3.0-atmel3.6.1-arduino7\\bin")


# Pass defines to compiler
add_definitions(
    -DF_CPU=${F_CPU}
    -DBAUD=${BAUD}
)
# mmcu MUST be passed to bot the compiler and linker, this handle the linker
set(CMAKE_EXE_LINKER_FLAGS -mmcu=${MCU})

add_compile_options(
    -mmcu=${MCU} # MCU
    -Os # optimize
    -Wall # enable warnings
    -Wno-main
    -Wundef
    -pedantic
    -Wstrict-prototypes
    -Werror
    -Wfatal-errors
    -Wl,--relax,--gc-sections
    -g
    -gdwarf-2
    -funsigned-char # a few optimizations
    -funsigned-bitfields
    -fpack-struct
    -fshort-enums
    -ffunction-sections
    -fdata-sections
    -fno-split-wide-types
    -fno-tree-scev-cprop
)
file(GLOB SRC_FILES "src/*.cpp" "src/*.c") # Load all files in src folder

# Create one target
add_executable(${PRODUCT_NAME} ${SRC_FILES})

# Rename the output to .elf as we will create multiple files
set_target_properties(${PRODUCT_NAME} PROPERTIES OUTPUT_NAME ${PRODUCT_NAME}.elf)

# Strip binary for upload
add_custom_target(strip ALL avr-strip ${PRODUCT_NAME}.elf DEPENDS ${PRODUCT_NAME})

# Transform binary into hex file, we ignore the eeprom segments in the step
add_custom_target(hex ALL avr-objcopy -R .eeprom -O ihex ${PRODUCT_NAME}.elf ${PRODUCT_NAME}.hex DEPENDS strip)
# Transform binary into hex file, this is the eeprom part (empty if you don't
# use eeprom static variables)
add_custom_target(eeprom avr-objcopy -j .eeprom  --set-section-flags=.eeprom="alloc,load"  --change-section-lma .eeprom=0 -O ihex ${PRODUCT_NAME}.elf ${PRODUCT_NAME}.eep DEPENDS strip)

# Clean extra files
set_directory_properties(PROPERTIES ADDITIONAL_MAKE_CLEAN_FILES "${PRODUCT_NAME}.hex;${PRODUCT_NAME}.eeprom;${PRODUCT_NAME}.lst")

验证步骤 #

1. 删除已有的build_atmega328目录
2. 重新运行原来的CMake配置命令
3. 检查输出，确认编译器检测通过，没有--out-implib相关错误

内容的提问来源于stack exchange，提问作者Tomáš Zato