boehm::ffi::GC_call_with_gc_active
pub extern fn GC_call_with_gc_active(arg1: GC_fn_type, arg2: *mut c_void) -> *mut c_void
pub extern fn GC_call_with_gc_active(arg1: GC_fn_type, arg2: *mut c_void) -> *mut c_void
                Prefix searches with a type followed by a colon (e.g.
                fn:) to restrict the search to a given type.
            
                Accepted types are: fn, mod,
                struct (or str), enum,
                trait, typedef (or
                tdef).