pub unsafe extern "C" fn pango_shape_with_flags(
    item_text: *const c_char,
    item_length: c_int,
    paragraph_text: *const c_char,
    paragraph_length: c_int,
    analysis: *const PangoAnalysis,
    glyphs: *mut PangoGlyphString,
    flags: PangoShapeFlags
)
This is supported on crate feature v1_44 only.