+MSVC_DIAG_IGNORE(4756 4056)
+PERL_STATIC_INLINE
+double S_Infinity() {
+ /* this is a real C literal which can get further constant folded
+ unlike using HUGE_VAL/_HUGE which are data symbol imports from the CRT
+ and therefore can not by folded by VC, an example of constant
+ folding INF is creating -INF */
+ return (DBL_MAX+DBL_MAX);
+}
+MSVC_DIAG_RESTORE
+
+#define NV_INF S_Infinity()
+
+/* selectany allows duplicate and unused data symbols to be removed by
+ VC linker, if this were static, each translation unit will have its own,
+ usually unused __PL_nan_u, if this were plain extern it will cause link
+ to fail due to multiple definitions, since we dont know if we are being
+ compiled as static or DLL XS, selectany simply always works, the cost of
+ importing __PL_nan_u across DLL boundaries in size in the importing DLL
+ will be more than the 8 bytes it will take up being in each XS DLL if
+ that DLL actually uses __PL_nan_u */
+union PerlNan { unsigned __int64 __q; double __d; };
+extern const __declspec(selectany) union PerlNan __PL_nan_u = { 0x7FF8000000000000UI64 };
+#define NV_NAN ((NV)__PL_nan_u.__d)
+
+#endif /* ifdef _MSC_VER */
+
+/* The CRT was rewritten in VS2015. */
+#ifdef _UCRT
+
+/* No longer declared in stdio.h */
+EXTERN_C char *gets(char* buffer);
+
+#define tzname _tzname
+
+/* From corecrt_internal_stdio.h: */
+typedef struct
+{
+ union
+ {
+ FILE _public_file;
+ char* _ptr;
+ } u;
+
+ char* _base;
+ int _cnt;
+ long _flags;
+ long _file;
+ int _charbuf;
+ int _bufsiz;
+ char* _tmpfname;
+ CRITICAL_SECTION _lock;
+} __crt_stdio_stream_data;
+
+#define PERLIO_FILE_flag_RD 0x0001 /* _IOREAD */
+#define PERLIO_FILE_flag_WR 0x0002 /* _IOWRITE */
+#define PERLIO_FILE_flag_RW 0x0004 /* _IOUPDATE */
+#define PERLIO_FILE_ptr(f) (((__crt_stdio_stream_data*)(f))->u._ptr)
+#define PERLIO_FILE_base(f) (((__crt_stdio_stream_data*)(f))->_base)
+#define PERLIO_FILE_cnt(f) (((__crt_stdio_stream_data*)(f))->_cnt)
+#define PERLIO_FILE_flag(f) ((int)(((__crt_stdio_stream_data*)(f))->_flags))
+#define PERLIO_FILE_file(f) (*(int*)(&((__crt_stdio_stream_data*)(f))->_file))
+
+#else /* ifdef _UCRT */
+
+/* Note: PERLIO_FILE_ptr/base/cnt are not actually used for GCC or <VS2015
+ * since FILE_ptr/base/cnt do the same thing anyway but it doesn't hurt to
+ * define them all here for completeness. */
+#define PERLIO_FILE_flag_RD _IOREAD /* 0x001 */
+#define PERLIO_FILE_flag_WR _IOWRT /* 0x002 */
+#define PERLIO_FILE_flag_RW _IORW /* 0x080 */
+#define PERLIO_FILE_ptr(f) ((f)->_ptr)
+#define PERLIO_FILE_base(f) ((f)->_base)
+#define PERLIO_FILE_cnt(f) ((f)->_cnt)
+#define PERLIO_FILE_flag(f) ((f)->_flag)
+#define PERLIO_FILE_file(f) ((f)->_file)