编译 32 位和 64 位

Question

我正在尝试在同一个 CMakeLists.txt 文件中为 32 位和 64 位编译一些代码。我认为最简单的方法是使用函数。编译中使用的（静态）库也在 CMakeLists.txt 文件中构建。然而，尽管在不同的目录中构建它们，CMake 抱怨：

add_library cannot create target "mylib" because another target with
the same name already exists.  The existing target is a static library
created in source directory "/home/chris/proj".

问题代码是：

cmake_minimum_required (VERSION 2.6 FATAL_ERROR)

enable_language(Fortran)
project(myproj)

set(libfolder ${PROJECT_SOURCE_DIR}/lib/)

function(build bit)

  message("Build library")
  set(BUILD_BINARY_DIR ${PROJECT_BINARY_DIR}/rel-${bit})
  set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${BUILD_BINARY_DIR}/bin)
  add_library(mylib STATIC ${libfolder}/mylib.for)
  set(CMAKE_Fortran_FLAGS "-m${bit}")

endfunction()

build(32)
build(64)

我确定我遗漏了一些明显的东西，但看不到问题......

Answer 1

正如我在评论中所说，这是我们如何做到这一点的一个例子。

if( CMAKE_SIZEOF_VOID_P EQUAL 8 )
    MESSAGE( "64 bits compiler detected" )
    SET( EX_PLATFORM 64 )
    SET( EX_PLATFORM_NAME "x64" )
else( CMAKE_SIZEOF_VOID_P EQUAL 8 ) 
    MESSAGE( "32 bits compiler detected" )
    SET( EX_PLATFORM 32 )
    SET( EX_PLATFORM_NAME "x86" )
endif( CMAKE_SIZEOF_VOID_P EQUAL 8 )

... 

IF( EX_PLATFORM EQUAL 64 )
MESSAGE( "Outputting to lib64 and bin64" )

# ---------- Setup output Directories -------------------------
SET (CMAKE_LIBRARY_OUTPUT_DIRECTORY
   ${YourSoftwarePath}/lib64
   CACHE PATH
   "Single Directory for all Libraries"
   )

# --------- Setup the Executable output Directory -------------
SET (CMAKE_RUNTIME_OUTPUT_DIRECTORY
   ${YourSoftwarePath}/bin64
   CACHE PATH
   "Single Directory for all Executables."
   )

# --------- Setup the Executable output Directory -------------
SET (CMAKE_ARCHIVE_OUTPUT_DIRECTORY
   ${YourSoftwarePath}/lib64
   CACHE PATH
   "Single Directory for all static libraries."
   )
ELSE( EX_PLATFORM EQUAL 64 )
# ---------- Setup output Directories -------------------------
SET (CMAKE_LIBRARY_OUTPUT_DIRECTORY
   ${YourSoftwarePath}/lib
   CACHE PATH
   "Single Directory for all Libraries"
   )

# --------- Setup the Executable output Directory -------------
SET (CMAKE_RUNTIME_OUTPUT_DIRECTORY
   ${YourSoftwarePath}/bin
   CACHE PATH
   "Single Directory for all Executables."
   )

# --------- Setup the Executable output Directory -------------
SET (CMAKE_ARCHIVE_OUTPUT_DIRECTORY
   ${YourSoftwarePath}/lib
   CACHE PATH
   "Single Directory for all static libraries."
   )
ENDIF( EX_PLATFORM EQUAL 64 )

...


add_library(YourSoftware SHARED
    ${INCLUDES}
    ${SRC}
)

即使在我们的生产过程中，它也对我们运作良好。

它允许 top 为 32 位和 64 位准备好我们的配置。之后我们必须在两个平台上进行构建。