Use IWYU.

tools/iwyu.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+cd "$(dirname "$0")"
+cd ..
+mapping_dir=$(pwd)
+mkdir -p iwyu
+cd iwyu
+rm * -rf
+echo $CMAKE_CXX_INCLUDE_WHAT_YOU_USE
+cmake .. -DFTXUI_BUILD_TESTS=ON -DCMAKE_CXX_INCLUDE_WHAT_YOU_USE="iwyu;-Xiwyu;--cxx17ns;-Xiwyu;--mapping_file=${mapping_dir}/iwyu.imp;-Xiwyu;--verbose=3"
+make -j 2>out
+fix_include --comments < out