+# if INTSIZE == 4
+/* At this point we assume the IEEE 754 floating point (and of course,
+ * we also assume a floating point format that can encode an infinity).
+ * We will coerce an int32 (which will encode the infinity) into
+ * a 32-bit float, which will then be cast into NV.
+ *
+ * Note that we intentionally use a float and 32-bit int, instead of
+ * shifting a small integer into a full IV, and from that into a full
+ * NV, because:
+ *
+ * (1) an IV might not be wide enough to cover all the bits of an NV.
+ * (2) the exponent part (including the infinity and nan bits) of a NV
+ * might be wider than just 16 bits.
+ *
+ * Below the NV_NAN logic has similar __PL_nan_u fallback, the only
+ * difference being the int32 constant being coerced. */
+# define __PL_inf_float_int32 0x7F800000
+static const union { unsigned int __i; float __f; } __PL_inf_u =
+ { __PL_inf_float_int32 };
+# define NV_INF ((NV)(__PL_inf_u.__f))
+# endif
+#endif
+#if !defined(NV_INF)