How to Correctly Add Linker or Compile Flags in CMake?

How to Add Linker or Compile Flags in a CMake File

Problem Statement

When compiling a simple program with exception handling using the arm-linux-androideabi-g compiler, the -fexceptions flag must be added to enable exception handling. However, attempts to add this flag through CMake using set(CMAKE_EXE_LINKER_FLAGS) or set(CMAKE_C_FLAGS) result in an error.

Solution

To add linker or compile flags in a CMake file, follow these steps:

1. Define the flags: Use the following commands to define the -fexceptions flag:

   SET(FLAG_NAME -fexceptions)

2. Append to CMake variables: Add the flag to the relevant CMake variables. For compiler flags:

   SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${FLAG_NAME}")
   SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${FLAG_NAME}")

   For linker flags:

   SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${FLAG_NAME}")
   SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${FLAG_NAME}")

3. Use target properties: Alternatively, you can use target properties:

   get_target_property(TEMP ${TARGET} COMPILE_FLAGS)
   if(TEMP STREQUAL "TEMP-NOTFOUND")
     SET(TEMP "")
   else()
     SET(TEMP "${TEMP} ")
   endif()
   SET(TEMP "${TEMP}${FLAG_NAME}")
   set_target_properties(${TARGET} PROPERTIES COMPILE_FLAGS ${TEMP})

4. Choose a method: Select one of the provided methods based on your preferences. Method 2 is generally recommended.

By following these steps, you can successfully add linker or compile flags in a CMake file and resolve the issue of enabling exception handling with the -fexceptions flag.

The above is the detailed content of How to Correctly Add Linker or Compile Flags in CMake?. For more information, please follow other related articles on the PHP Chinese website!