CheckOBJCXXSourceCompiles

在 3.16 版被加入.

This module provides a command to check whether an Objective-C++ source can be built.

在 CMake 專案中使用以下命令載入該模組：

include(CheckOBJCXXSourceCompiles)

命令

This module provides the following command:

check_objcxx_source_compiles

Checks once whether the given Objective-C++ source code can be built:

check_objcxx_source_compiles(<code> <variable> [FAIL_REGEX <regexes>...])

This command checks once that the source supplied in <code> can be compiled (and linked into an executable). The result of the check is stored in the internal cache variable specified by <variable>.

The arguments are:

<code>

Objective-C++ source code to check. This must be an entire program, as written in a file containing the body block. All symbols used in the source code are expected to be declared as usual in their corresponding headers.

<variable>

Variable name of an internal cache variable to store the result of the check, with boolean true for success and boolean false for failure.

FAIL_REGEX <regexes>...

If this option is provided with one or more regular expressions, then failure is determined by checking if anything in the compiler output matches any of the specified regular expressions.

影響檢查的變數

可以在呼叫此命令之前設定以下變數，以修改檢查的執行方式：

CMAKE_REQUIRED_FLAGS

一個以空格分隔的字串，包含要傳遞給編譯器的額外旗標。分號分隔列表將無法運作。CMAKE_<LANG>_FLAGS 及其關聯的特定組態 CMAKE_<LANG>_FLAGS_<CONFIG> 變數的內容會在該變數的內容之前自動預置到編譯器命令中。

CMAKE_REQUIRED_DEFINITIONS

一個編譯器定義的分號分隔列表，每個定義的形式為 -DFOO 或 -DFOO=bar。由檢查命令的結果變數引數所指定的名稱的定義也會自動新增。

CMAKE_REQUIRED_INCLUDES

一個要傳遞給編譯器的標頭搜尋路徑的分號分隔列表。這些將是唯一使用的標頭搜尋路徑；INCLUDE_DIRECTORIES 目錄屬性的內容將被忽略。

CMAKE_REQUIRED_LINK_OPTIONS

在 3.14 版被加入.

一個要新增到連結命令的選項的分號分隔列表（詳情請參見 try_compile()）。

CMAKE_REQUIRED_LIBRARIES

一個要新增到連結命令的程式庫的分號分隔列表。這些可以是系統程式庫的名稱，也可以是 Imported Targets`（詳情請參見 :command:`try_compile）。

CMAKE_REQUIRED_LINK_DIRECTORIES

在 3.31 版被加入.

一個要傳遞給連結器的程式庫搜尋路徑的分號分隔列表（詳情請參見 try_compile()）。

CMAKE_REQUIRED_QUIET

在 3.1 版被加入.

如果此變數的值為布林真值，則與檢查相關的所有狀態訊息都將被抑制。

CMAKE_TRY_COMPILE_TARGET_TYPE

Internally, the try_compile() command is used to perform the check, and this variable controls the type of target it creates. If this variable is set to EXECUTABLE (the default), the check compiles and links the test source code as an executable program. If set to STATIC_LIBRARY, the test source code is compiled but not linked.

範例

In the following example, this module is used to check whether the provided Objective-C++ source code can be compiled and linked. Result of the check is stored in the internal cache variable HAVE_WORKING_CODE.

include(CheckOBJCXXSourceCompiles)

check_objcxx_source_compiles("
  #include <vector>
  #import <Foundation/Foundation.h>
  int main()
  {
    std::vector<int> v;
    NSObject *foo;
    return 0;
  }
" HAVE_WORKING_CODE)

另請參見

  • The CheckSourceCompiles module for a more general command to check whether source can be built.

  • The CheckSourceRuns module to check whether source can be built and run.