ions only supports the
  format strings defined in the C standard. Beware
  of <a class="underlined"
  href="https://bugs.llvm.org/show_bug.cgi?id=47665">this bug</a> when
  you use this function with clang. These functions are neither
  thread safe nor atomic.
</p>

<hr/>

<p class="funcname"><b id="Sleef_cast_to_doubleq1" class="func">Sleef_cast_to_doubleq1</b>, <b id="Sleef_cast_to_doubleq1_purec" class="func">Sleef_cast_to_doubleq1_purec</b>, <b id="Sleef_cast_to_doubleq1_purecfma" class="func">Sleef_ca