Function phper_sys::zend_string_concat3

pub unsafe extern "C" fn zend_string_concat3(
    str1: *const c_char,
    str1_len: usize,
    str2: *const c_char,
    str2_len: usize,
    str3: *const c_char,
    str3_len: usize
) -> *mut zend_string