+#define pWARN_STD NULL
+#define pWARN_ALL (((STRLEN*)0)+1) /* use warnings 'all' */
+#define pWARN_NONE (((STRLEN*)0)+2) /* no warnings 'all' */
+
+#define specialWARN(x) ((x) == pWARN_STD || (x) == pWARN_ALL || \
+ (x) == pWARN_NONE)
+
+/* if PL_warnhook is set to this value, then warnings die */
+#define PERL_WARNHOOK_FATAL (&PL_sv_placeholder)
+
+/* Warnings Categories added in Perl 5.008 */
+
+#define WARN_ALL 0
+#define WARN_CLOSURE 1
+#define WARN_DEPRECATED 2
+#define WARN_EXITING 3
+#define WARN_GLOB 4
+#define WARN_IO 5
+#define WARN_CLOSED 6
+#define WARN_EXEC 7
+#define WARN_LAYER 8
+#define WARN_NEWLINE 9
+#define WARN_PIPE 10
+#define WARN_UNOPENED 11
+#define WARN_MISC 12
+#define WARN_NUMERIC 13
+#define WARN_ONCE 14
+#define WARN_OVERFLOW 15
+#define WARN_PACK 16
+#define WARN_PORTABLE 17
+#define WARN_RECURSION 18
+#define WARN_REDEFINE 19
+#define WARN_REGEXP 20
+#define WARN_SEVERE 21
+#define WARN_DEBUGGING 22
+#define WARN_INPLACE 23
+#define WARN_INTERNAL 24
+#define WARN_MALLOC 25
+#define WARN_SIGNAL 26
+#define WARN_SUBSTR 27
+#define WARN_SYNTAX 28
+#define WARN_AMBIGUOUS 29
+#define WARN_BAREWORD 30
+#define WARN_DIGIT 31
+#define WARN_PARENTHESIS 32
+#define WARN_PRECEDENCE 33
+#define WARN_PRINTF 34
+#define WARN_PROTOTYPE 35
+#define WARN_QW 36
+#define WARN_RESERVED 37
+#define WARN_SEMICOLON 38
+#define WARN_TAINT 39
+#define WARN_THREADS 40
+#define WARN_UNINITIALIZED 41
+#define WARN_UNPACK 42
+#define WARN_UNTIE 43
+#define WARN_UTF8 44
+#define WARN_VOID 45
+
+/* Warnings Categories added in Perl 5.011 */
+
+#define WARN_IMPRECISION 46
+
+#define WARNsize 12
+#define WARN_ALLstring "\125\125\125\125\125\125\125\125\125\125\125\125"
+#define WARN_NONEstring "\0\0\0\0\0\0\0\0\0\0\0\0"
+
+#define isLEXWARN_on (PL_curcop->cop_warnings != pWARN_STD)
+#define isLEXWARN_off (PL_curcop->cop_warnings == pWARN_STD)
+#define isWARN_ONCE (PL_dowarn & (G_WARN_ON|G_WARN_ONCE))
+#define isWARN_on(c,x) (IsSet((U8 *)(c + 1), 2*(x)))
+#define isWARNf_on(c,x) (IsSet((U8 *)(c + 1), 2*(x)+1))
+
+#define DUP_WARNINGS(p) \
+ (specialWARN(p) ? (STRLEN*)(p) \
+ : (STRLEN*)CopyD(p, PerlMemShared_malloc(sizeof(*p)+*p), sizeof(*p)+*p, \
+ char))
+
+#define ckWARN(w) Perl_ckwarn(aTHX_ packWARN(w))
+#define ckWARN2(w1,w2) Perl_ckwarn(aTHX_ packWARN2(w1,w2))
+#define ckWARN3(w1,w2,w3) Perl_ckwarn(aTHX_ packWARN3(w1,w2,w3))
+#define ckWARN4(w1,w2,w3,w4) Perl_ckwarn(aTHX_ packWARN4(w1,w2,w3,w4))
+
+#define ckWARN_d(w) Perl_ckwarn_d(aTHX_ packWARN(w))
+#define ckWARN2_d(w1,w2) Perl_ckwarn_d(aTHX_ packWARN2(w1,w2))
+#define ckWARN3_d(w1,w2,w3) Perl_ckwarn_d(aTHX_ packWARN3(w1,w2,w3))
+#define ckWARN4_d(w1,w2,w3,w4) Perl_ckwarn_d(aTHX_ packWARN4(w1,w2,w3,w4))
+
+#define packWARN(a) (a )
+#define packWARN2(a,b) ((a) | ((b)<<8) )
+#define packWARN3(a,b,c) ((a) | ((b)<<8) | ((c)<<16) )
+#define packWARN4(a,b,c,d) ((a) | ((b)<<8) | ((c)<<16) | ((d) <<24))
+
+#define unpackWARN1(x) ((x) & 0xFF)
+#define unpackWARN2(x) (((x) >>8) & 0xFF)
+#define unpackWARN3(x) (((x) >>16) & 0xFF)
+#define unpackWARN4(x) (((x) >>24) & 0xFF)