/* Approximation of the length of the decimal representation of this type. */
#define decimal_length(x) ((int)(sizeof(x) * 2.56 + 0.5) + 1)
-#if defined(__sun__)
+#ifdef __MINGW64__
+#define _POSIX_C_SOURCE 1
+#elif defined(__sun__)
/*
* On Solaris, when _XOPEN_EXTENDED is set, its header file
* forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE