> I am exploring this FreeType font engine library, am wondering if the
> auto-fit(auto-hint) support for monochrome display as well?
No, (good) auto-hinting is not available for monochrome display.
> I get segmentation fault whenever I use this flag ->
> FT_LOAD_FORCE_AUTOHINT
>
> FT_LOAD_RENDER | FT_LOAD_MONOCHROME | FT_LOAD_FORCE_AUTOHINT
A segmentation fault shouldn't happen; I guess you are forgetting to
check a return value somewhere. If the problem persists please
provide a small stand-alone code snippet for testing purposes that I
can compile and run on the command line.
Werner