CMake是否支持宏或函数重载？多参数宏调用报错该如何处理？

尝试实现的宏定义 #

macro(OVERLOAD_TEST par1 par2)
  message ("Macro with two arguments")
endmacro()

macro(OVERLOAD_TEST par1 par2 par3)
  message ("Macro with three arguments")
endmacro()

宏调用代码 #

OVERLOAD_TEST("A" "B" "C")
OVERLOAD_TEST("A" "B")

报错信息 #

Macro with three arguments
CMake Error at CMakeLists.txt:59 (OVERLOAD_TEST):
OVERLOAD_TEST Macro invoked with incorrect arguments for macro named:
OVERLOAD_TEST

CMake不支持宏或函数的重载，你定义的第二个OVERLOAD_TEST宏会直接覆盖第一个。调用两个参数的版本时，实际匹配的是要求三个参数的宏，因此触发参数错误。

你应该改用CMake的可选参数特性，只定义一个宏来处理不同参数数量的情况。以下是两种实现方式：

方式1：通过ARGV变量判断参数数量 #

macro(OVERLOAD_TEST par1 par2)
  # 检查是否存在第三个可选参数
  if(ARGV2)
    message("Macro with three arguments: ${par1}, ${par2}, ${ARGV2}")
  else()
    message("Macro with two arguments: ${par1}, ${par2}")
  endif()
endmacro()

调用示例：

OVERLOAD_TEST("A" "B" "C") # 输出 Macro with three arguments: "A", "B", "C"
OVERLOAD_TEST("A" "B")     # 输出 Macro with two arguments: "A", "B"

方式2：用cmake_parse_arguments规范处理（适合复杂场景） #

include(CMakeParseArguments)

macro(OVERLOAD_TEST)
  cmake_parse_arguments(ARG "" "" "" ${ARGN})
  list(LENGTH ARGN arg_count)
  if(arg_count EQUAL 3)
    message("Macro with three arguments: ${ARGN}")
  elseif(arg_count EQUAL 2)
    message("Macro with two arguments: ${ARGN}")
  else()
    message(FATAL_ERROR "OVERLOAD_TEST requires 2 or 3 arguments")
  endif()
endmacro()

内容的提问来源于stack exchange，提问作者Vikash