Cargo Features

fltk-sys has no features set by default.

fltk-sys = { version = "1.4.32", features = ["system-fltk", "system-zlib", "enable-glwindow", "single-threaded", "cairoext", "fltk-config", "pkg-config"] }
fltk-shared use-ninja system-fltk
system-libpng system-libjpeg system-zlib
legacy-opengl fltk-bundled enable-glwindow
no-images no-pango no-gdiplus single-threaded
use-wayland static-msvcrt cairoext
fltk-config = cc

Features from optional dependencies

In crates that don't use the dep: syntax, optional dependencies automatically become Cargo features. These features may have been created by mistake, and this functionality may be removed in the future.

cc build fltk-config?