--- a/newlib/libc/stdbit/stdc_bit_ceil.c
+++ b/newlib/libc/stdbit/stdc_bit_ceil.c
@@ -23,16 +23,17 @@ stdc_bit_ceil_uc(unsigned char x)
       return (1U << (UINT_WIDTH - __builtin_clz(x - 1)));
}

-/* Ensure we don't shift 1U out of range. */
-_Static_assert(USHRT_WIDTH < UINT_WIDTH,
-    "stdc_bit_ceil_us needs USHRT_WIDTH < UINT_WIDTH");
-
unsigned short
stdc_bit_ceil_us(unsigned short x)
{
       if (x <= 1)
               return (1);

+#if USHRT_WIDTH == UINT_WIDTH
+       if (x > USHRT_MAX/2 + 1)
+               return (0);
+#endif
+
       return (1U << (UINT_WIDTH - __builtin_clz(x - 1)));
}