build: use CMAKE_POSITION_INDEPENDENT_CODE instead of -fPIC (#21947)

It's simpler to let cmake figure out what flags to add to each platforms
to create position independent code rather than handling it ourselves.

Also remove code that sets POSITION_INDEPENDENT_CODE property on SHARED
and MODULE libraries, as it's already on by default.

cmake.deps/cmake/BuildLibvterm.cmake

@@ -9,10 +9,8 @@ if(WIN32)
       -DCMAKE_INSTALL_PREFIX=${DEPS_INSTALL_DIR}
       -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
       -DCMAKE_GENERATOR_PLATFORM=${CMAKE_GENERATOR_PLATFORM}
-      -DCMAKE_GENERATOR=${CMAKE_GENERATOR})
-  if(NOT MSVC)
-    list(APPEND LIBVTERM_CONFIGURE_COMMAND "-DCMAKE_C_FLAGS:STRING=-fPIC")
-  endif()
+      -DCMAKE_GENERATOR=${CMAKE_GENERATOR}
+      -DCMAKE_POSITION_INDEPENDENT_CODE=ON)
   set(LIBVTERM_BUILD_COMMAND ${CMAKE_COMMAND} --build . --config $<CONFIG>)
   set(LIBVTERM_INSTALL_COMMAND ${CMAKE_COMMAND} --build . --target install --config $<CONFIG>)
 else()

cmake.deps/cmake/BuildLuv.cmake

@@ -12,7 +12,8 @@ set(LUV_CMAKE_ARGS
   -DWITH_SHARED_LIBUV=ON
   -DBUILD_SHARED_LIBS=OFF
   -DBUILD_STATIC_LIBS=ON
-  -DBUILD_MODULE=OFF)
+  -DBUILD_MODULE=OFF
+  -DCMAKE_POSITION_INDEPENDENT_CODE=ON)
 
 if(USE_BUNDLED_LUAJIT)
   list(APPEND LUV_CMAKE_ARGS -DWITH_LUA_ENGINE=LuaJit)
@@ -33,16 +34,11 @@ if(USE_BUNDLED_LIBUV)
     -DLIBUV_LIBRARIES=uv_a)
 endif()
 
-if(MSVC)
-  list(APPEND LUV_CMAKE_ARGS
-    "-DCMAKE_C_FLAGS:STRING=${LUV_INCLUDE_FLAGS}")
-else()
-  list(APPEND LUV_CMAKE_ARGS
-    "-DCMAKE_C_FLAGS:STRING=${LUV_INCLUDE_FLAGS} -fPIC")
-  if(CMAKE_GENERATOR MATCHES "Unix Makefiles" AND
-      (CMAKE_SYSTEM_NAME MATCHES ".*BSD" OR CMAKE_SYSTEM_NAME MATCHES "DragonFly"))
-      list(APPEND LUV_CMAKE_ARGS -DCMAKE_MAKE_PROGRAM=gmake)
-  endif()
+list(APPEND LUV_CMAKE_ARGS
+  "-DCMAKE_C_FLAGS:STRING=${LUV_INCLUDE_FLAGS}")
+if(CMAKE_GENERATOR MATCHES "Unix Makefiles" AND
+    (CMAKE_SYSTEM_NAME MATCHES ".*BSD" OR CMAKE_SYSTEM_NAME MATCHES "DragonFly"))
+    list(APPEND LUV_CMAKE_ARGS -DCMAKE_MAKE_PROGRAM=gmake)
 endif()
 
 if(USE_EXISTING_SRC_DIR)

cmake.deps/cmake/BuildMsgpack.cmake

@@ -5,13 +5,9 @@ set(MSGPACK_CMAKE_ARGS
     -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
     -DCMAKE_GENERATOR=${CMAKE_GENERATOR}
     -DCMAKE_GENERATOR_PLATFORM=${CMAKE_GENERATOR_PLATFORM}
+    -DCMAKE_POSITION_INDEPENDENT_CODE=ON
     ${BUILD_TYPE_STRING})
 
-if(NOT MSVC)
-  list(APPEND MSGPACK_CMAKE_ARGS
-    "-DCMAKE_C_FLAGS:STRING=-fPIC")
-endif()
-
 if(USE_EXISTING_SRC_DIR)
   unset(MSGPACK_URL)
 endif()

cmake.deps/cmake/TreesitterParserCMakeLists.txt

@@ -11,7 +11,6 @@ add_library(parser
 set_target_properties(
   parser
   PROPERTIES
-    POSITION_INDEPENDENT_CODE ON
     OUTPUT_NAME ${PARSERLANG}
     PREFIX ""
 )

src/nvim/CMakeLists.txt

@@ -861,7 +861,6 @@ endif()
 set_target_properties(
   libnvim
   PROPERTIES
-    POSITION_INDEPENDENT_CODE ON
     OUTPUT_NAME ${LIBNVIM_NAME}
 )
 target_compile_definitions(libnvim PRIVATE MAKE_LIB)
@@ -885,11 +884,6 @@ else()
     target_link_libraries(nvim-test PRIVATE "-framework CoreServices")
   endif()
   target_include_directories(nvim-test PRIVATE ${LUAJIT_INCLUDE_DIRS})
-  set_target_properties(
-    nvim-test
-    PROPERTIES
-      POSITION_INDEPENDENT_CODE ON
-  )
   target_compile_definitions(nvim-test PRIVATE UNIT_TESTING)
 endif()