Compiling a static executable with CMake

Add these lines after add_executable(MyExec "main.c") (for example) :

target_link_libraries(MyExec PUBLIC "-static")

or before: link_libraries("-static")

As global CMake settings, add these lines before add_executable, valid for gcc/clang:

set(CMAKE_FIND_LIBRARY_SUFFIXES ".a")
set(BUILD_SHARED_LIBS OFF)
set(CMAKE_EXE_LINKER_FLAGS "-static")

On Modern CMake (3.x+ - target_link_libraries doc), you can apply the flag to specific targets, in this way:

target_link_libraries(your_target_name -static)

If you're using MSVC, you have to set the compiler and linker flags:

set(CMAKE_FIND_LIBRARY_SUFFIXES ".lib")
target_compile_options(your_target_name [PUBLIC|PRIVATE] /MT)
target_link_options(your_target_name [PUBLIC|PRIVATE] /INCREMENTAL:NO /NODEFAULTLIB:MSVCRT)

or alternatively also:

set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")

and if you are using MFC, you need to specify the flag to 1 see here:

set(CMAKE_MFC_FLAG 1)