使用 Cmake 构建 asmJit 示例

Question

我正在尝试构建一个基于 asmJit 的示例项目。

我有以下设置 AsmTest

• 主程序
• CmakeLists.txt
• 库
  • asmjit（里面是来自 github 存储库的 CmakeList.txt）。
  • CMakeLists.txt（内容：add_subdirectory(asmjit)）
• 建造

我的第一个CmakeLists.txt的内容是：

cmake_minimum_required(VERSION 2.8)
project(asmJitTest)

add_subdirectory(libs)
include_directories(${asmJitTest_SOURCE_DIR} ${asmJitTest_SOURCE_DIR}/libs/asmjit/src)
add_executable(JitTest main.cpp)
target_link_libraries(JitTest asmjit)

我可以成功构建这个项目，获得视觉工作室解决方案。但是，如果我尝试在视觉工作室中运行它，我会收到各种“未解决的外部错误”，例如这样。

1   error LNK2001: unresolved external symbol "struct asmjit::X86RegData   
    const asmjit::x86RegData" (?x86RegData@asmjit@@3UX86RegData@1@B)    main.obj    JitTest

我不明白为什么会出现链接错误。我是 cmake 的新手，这整个过程是从头开始的。有人可以指出我正确的方向吗？

Answer 1

您可以将 asmjit 编译为动态链接库，只需将其包含CMakeLists.txt在您的 cmake 脚本中即可：

Set(ASMJIT_DIR "/relative/dir/to/your/asmjit")
Include("${ASMJIT_DIR}/CMakeLists.txt")

# AsmJit should have already taken care of include directories, if you
# are not sure you can add it, but shouldn't be necessary.
Include_Directories(${ASMJIT_DIR})

# Then in your target you should be able to use:
Target_Link_Libraries(YourTarget asmjit ${ASMJIT_DEPS})

或者，我发现这对于将 asmjit 作为静态库嵌入更可靠，将整个 asmjit 嵌入到您的项目中。AsmJit 对此有内置支持：

# Tell asmjit that it will be embedded.
Set(ASMJIT_EMBED TRUE)
Add_Definitions(-DASMJIT_STATIC)

Set(ASMJIT_DIR "/relative/dir/to/your/asmjit")
Include("${ASMJIT_DIR}/CMakeLists.txt")

# If you add a library / executable, include asmjit sources.
Add_Executable(YourTarget main.cpp ${ASMJIT_SRC})

# You still have to include asmjit dependencies.
Target_Link_Libraries(YourTarget ${ASMJIT_DEPS})

与动态或静态构建 asmjit 相比，第二种方法有一个很大的优势，即它可以通过这种方式嵌入到动态链接库中，而不会在 Linux 和所有需要使用的平台下出现问题-fPIC，因为默认情况下 cmake 不会将其放入-fPIC静态库构建，但这将需要更长的讨论，并且与您的问题并不真正相关。