Re: What sort of Makefile.PL should h2xs write?

Message-ID: <20010923230055.Y4971@plum.flirble.org>

(with "sample_constants" changed to "fallback")

p4raw-id: //depot/perl@12169

4 files changed, 838 insertions, 810 deletions

diff --git a/ext/I18N/Langinfo/Langinfo.xs b/ext/I18N/Langinfo/Langinfo.xs
index 3dd0738d5e..d335eec71e 100644
--- a/ext/I18N/Langinfo/Langinfo.xs
+++ b/ext/I18N/Langinfo/Langinfo.xs
@@ -6,821 +6,13 @@
 #   include <langinfo.h>
 #endif
 
-#define PERL_constant_NOTFOUND	1
-#define PERL_constant_NOTDEF	2
-#define PERL_constant_ISIV	3
-#define PERL_constant_ISNO	4
-#define PERL_constant_ISNV	5
-#define PERL_constant_ISPV	6
-#define PERL_constant_ISPVN	7
-#define PERL_constant_ISSV	8
-#define PERL_constant_ISUNDEF	9
-#define PERL_constant_ISUV	10
-#define PERL_constant_ISYES	11
-
-#ifndef NVTYPE
-typedef double NV; /* 5.6 and later define NVTYPE, and typedef NV to it.  */
-#endif
-static int
-constant_5 (pTHX_ const char *name, IV *iv_return) {
-  /* When generated this function returned values for the list of names given
-     here.  However, subsequent manual editing may have added or removed some.
-     DAY_1 DAY_2 DAY_3 DAY_4 DAY_5 DAY_6 DAY_7 D_FMT MON_1 MON_2 MON_3 MON_4
-     MON_5 MON_6 MON_7 MON_8 MON_9 NOSTR T_FMT */
-  /* Offset 4 gives the best switch position.  */
-  switch (name[4]) {
-  case '1':
-    if (memEQ(name, "DAY_1", 5)) {
-    /*                   ^      */
-#ifdef DAY_1
-      *iv_return = DAY_1;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_1", 5)) {
-    /*                   ^      */
-#ifdef MON_1
-      *iv_return = MON_1;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '2':
-    if (memEQ(name, "DAY_2", 5)) {
-    /*                   ^      */
-#ifdef DAY_2
-      *iv_return = DAY_2;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_2", 5)) {
-    /*                   ^      */
-#ifdef MON_2
-      *iv_return = MON_2;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '3':
-    if (memEQ(name, "DAY_3", 5)) {
-    /*                   ^      */
-#ifdef DAY_3
-      *iv_return = DAY_3;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_3", 5)) {
-    /*                   ^      */
-#ifdef MON_3
-      *iv_return = MON_3;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '4':
-    if (memEQ(name, "DAY_4", 5)) {
-    /*                   ^      */
-#ifdef DAY_4
-      *iv_return = DAY_4;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_4", 5)) {
-    /*                   ^      */
-#ifdef MON_4
-      *iv_return = MON_4;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '5':
-    if (memEQ(name, "DAY_5", 5)) {
-    /*                   ^      */
-#ifdef DAY_5
-      *iv_return = DAY_5;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_5", 5)) {
-    /*                   ^      */
-#ifdef MON_5
-      *iv_return = MON_5;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '6':
-    if (memEQ(name, "DAY_6", 5)) {
-    /*                   ^      */
-#ifdef DAY_6
-      *iv_return = DAY_6;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_6", 5)) {
-    /*                   ^      */
-#ifdef MON_6
-      *iv_return = MON_6;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '7':
-    if (memEQ(name, "DAY_7", 5)) {
-    /*                   ^      */
-#ifdef DAY_7
-      *iv_return = DAY_7;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_7", 5)) {
-    /*                   ^      */
-#ifdef MON_7
-      *iv_return = MON_7;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '8':
-    if (memEQ(name, "MON_8", 5)) {
-    /*                   ^      */
-#ifdef MON_8
-      *iv_return = MON_8;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '9':
-    if (memEQ(name, "MON_9", 5)) {
-    /*                   ^      */
-#ifdef MON_9
-      *iv_return = MON_9;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'R':
-    if (memEQ(name, "NOSTR", 5)) {
-    /*                   ^      */
-#ifdef NOSTR
-      *iv_return = NOSTR;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'T':
-    if (memEQ(name, "D_FMT", 5)) {
-    /*                   ^      */
-#ifdef D_FMT
-      *iv_return = D_FMT;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "T_FMT", 5)) {
-    /*                   ^      */
-#ifdef T_FMT
-      *iv_return = T_FMT;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  }
-  return PERL_constant_NOTFOUND;
-}
-
-static int
-constant_6 (pTHX_ const char *name, IV *iv_return) {
-  /* When generated this function returned values for the list of names given
-     here.  However, subsequent manual editing may have added or removed some.
-     AM_STR MON_10 MON_11 MON_12 NOEXPR PM_STR YESSTR */
-  /* Offset 0 gives the best switch position.  */
-  switch (name[0]) {
-  case 'A':
-    if (memEQ(name, "AM_STR", 6)) {
-    /*               ^           */
-#ifdef AM_STR
-      *iv_return = AM_STR;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'M':
-    if (memEQ(name, "MON_10", 6)) {
-    /*               ^           */
-#ifdef MON_10
-      *iv_return = MON_10;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_11", 6)) {
-    /*               ^           */
-#ifdef MON_11
-      *iv_return = MON_11;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "MON_12", 6)) {
-    /*               ^           */
-#ifdef MON_12
-      *iv_return = MON_12;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'N':
-    if (memEQ(name, "NOEXPR", 6)) {
-    /*               ^           */
-#ifdef NOEXPR
-      *iv_return = NOEXPR;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'P':
-    if (memEQ(name, "PM_STR", 6)) {
-    /*               ^           */
-#ifdef PM_STR
-      *iv_return = PM_STR;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'Y':
-    if (memEQ(name, "YESSTR", 6)) {
-    /*               ^           */
-#ifdef YESSTR
-      *iv_return = YESSTR;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  }
-  return PERL_constant_NOTFOUND;
-}
-
-static int
-constant_7 (pTHX_ const char *name, IV *iv_return) {
-  /* When generated this function returned values for the list of names given
-     here.  However, subsequent manual editing may have added or removed some.
-     ABDAY_1 ABDAY_2 ABDAY_3 ABDAY_4 ABDAY_5 ABDAY_6 ABDAY_7 ABMON_1 ABMON_2
-     ABMON_3 ABMON_4 ABMON_5 ABMON_6 ABMON_7 ABMON_8 ABMON_9 CODESET D_T_FMT
-     THOUSEP YESEXPR */
-  /* Offset 6 gives the best switch position.  */
-  switch (name[6]) {
-  case '1':
-    if (memEQ(name, "ABDAY_1", 7)) {
-    /*                     ^      */
-#ifdef ABDAY_1
-      *iv_return = ABDAY_1;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "ABMON_1", 7)) {
-    /*                     ^      */
-#ifdef ABMON_1
-      *iv_return = ABMON_1;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '2':
-    if (memEQ(name, "ABDAY_2", 7)) {
-    /*                     ^      */
-#ifdef ABDAY_2
-      *iv_return = ABDAY_2;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "ABMON_2", 7)) {
-    /*                     ^      */
-#ifdef ABMON_2
-      *iv_return = ABMON_2;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '3':
-    if (memEQ(name, "ABDAY_3", 7)) {
-    /*                     ^      */
-#ifdef ABDAY_3
-      *iv_return = ABDAY_3;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "ABMON_3", 7)) {
-    /*                     ^      */
-#ifdef ABMON_3
-      *iv_return = ABMON_3;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '4':
-    if (memEQ(name, "ABDAY_4", 7)) {
-    /*                     ^      */
-#ifdef ABDAY_4
-      *iv_return = ABDAY_4;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "ABMON_4", 7)) {
-    /*                     ^      */
-#ifdef ABMON_4
-      *iv_return = ABMON_4;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '5':
-    if (memEQ(name, "ABDAY_5", 7)) {
-    /*                     ^      */
-#ifdef ABDAY_5
-      *iv_return = ABDAY_5;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "ABMON_5", 7)) {
-    /*                     ^      */
-#ifdef ABMON_5
-      *iv_return = ABMON_5;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '6':
-    if (memEQ(name, "ABDAY_6", 7)) {
-    /*                     ^      */
-#ifdef ABDAY_6
-      *iv_return = ABDAY_6;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "ABMON_6", 7)) {
-    /*                     ^      */
-#ifdef ABMON_6
-      *iv_return = ABMON_6;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '7':
-    if (memEQ(name, "ABDAY_7", 7)) {
-    /*                     ^      */
-#ifdef ABDAY_7
-      *iv_return = ABDAY_7;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "ABMON_7", 7)) {
-    /*                     ^      */
-#ifdef ABMON_7
-      *iv_return = ABMON_7;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '8':
-    if (memEQ(name, "ABMON_8", 7)) {
-    /*                     ^      */
-#ifdef ABMON_8
-      *iv_return = ABMON_8;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '9':
-    if (memEQ(name, "ABMON_9", 7)) {
-    /*                     ^      */
-#ifdef ABMON_9
-      *iv_return = ABMON_9;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'P':
-    if (memEQ(name, "THOUSEP", 7)) {
-    /*                     ^      */
-#ifdef THOUSEP
-      *iv_return = THOUSEP;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'R':
-    if (memEQ(name, "YESEXPR", 7)) {
-    /*                     ^      */
-#ifdef YESEXPR
-      *iv_return = YESEXPR;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'T':
-    if (memEQ(name, "CODESET", 7)) {
-    /*                     ^      */
-#ifdef CODESET
-      *iv_return = CODESET;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    if (memEQ(name, "D_T_FMT", 7)) {
-    /*                     ^      */
-#ifdef D_T_FMT
-      *iv_return = D_T_FMT;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  }
-  return PERL_constant_NOTFOUND;
-}
-
-static int
-constant_8 (pTHX_ const char *name, IV *iv_return) {
-  /* When generated this function returned values for the list of names given
-     here.  However, subsequent manual editing may have added or removed some.
-     ABMON_10 ABMON_11 ABMON_12 CRNCYSTR */
-  /* Offset 7 gives the best switch position.  */
-  switch (name[7]) {
-  case '0':
-    if (memEQ(name, "ABMON_10", 8)) {
-    /*                      ^      */
-#ifdef ABMON_10
-      *iv_return = ABMON_10;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '1':
-    if (memEQ(name, "ABMON_11", 8)) {
-    /*                      ^      */
-#ifdef ABMON_11
-      *iv_return = ABMON_11;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case '2':
-    if (memEQ(name, "ABMON_12", 8)) {
-    /*                      ^      */
-#ifdef ABMON_12
-      *iv_return = ABMON_12;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'R':
-    if (memEQ(name, "CRNCYSTR", 8)) {
-    /*                      ^      */
-#ifdef CRNCYSTR
-      *iv_return = CRNCYSTR;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  }
-  return PERL_constant_NOTFOUND;
-}
-
-static int
-constant_9 (pTHX_ const char *name, IV *iv_return) {
-  /* When generated this function returned values for the list of names given
-     here.  However, subsequent manual editing may have added or removed some.
-     ERA_D_FMT ERA_T_FMT RADIXCHAR */
-  /* Offset 4 gives the best switch position.  */
-  switch (name[4]) {
-  case 'D':
-    if (memEQ(name, "ERA_D_FMT", 9)) {
-    /*                   ^          */
-#ifdef ERA_D_FMT
-      *iv_return = ERA_D_FMT;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'T':
-    if (memEQ(name, "ERA_T_FMT", 9)) {
-    /*                   ^          */
-#ifdef ERA_T_FMT
-      *iv_return = ERA_T_FMT;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 'X':
-    if (memEQ(name, "RADIXCHAR", 9)) {
-    /*                   ^          */
-#ifdef RADIXCHAR
-      *iv_return = RADIXCHAR;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  }
-  return PERL_constant_NOTFOUND;
-}
-
-static int
-constant (pTHX_ const char *name, STRLEN len, IV *iv_return) {
-  /* Initially switch on the length of the name.  */
-  /* When generated this function returned values for the list of names given
-     in this section of perl code.  Rather than manually editing these functions
-     to add or remove constants, which would result in this comment and section
-     of code becoming inaccurate, we recommend that you edit this section of
-     code, and use it to regenerate a new set of constant functions which you
-     then use to replace the originals.
-
-     Regenerate these constant functions by feeding this entire source file to
-     perl -x
-
-#!../../../perl -w
-use ExtUtils::Constant qw (constant_types C_constant XS_constant);
-
-my $types = {map {($_, 1)} qw(IV)};
-my @names = (qw(ABDAY_1 ABDAY_2 ABDAY_3 ABDAY_4 ABDAY_5 ABDAY_6 ABDAY_7 ABMON_1
-	       ABMON_10 ABMON_11 ABMON_12 ABMON_2 ABMON_3 ABMON_4 ABMON_5
-	       ABMON_6 ABMON_7 ABMON_8 ABMON_9 ALT_DIGITS AM_STR CODESET
-	       CRNCYSTR DAY_1 DAY_2 DAY_3 DAY_4 DAY_5 DAY_6 DAY_7 D_FMT D_T_FMT
-	       ERA ERA_D_FMT ERA_D_T_FMT ERA_T_FMT MON_1 MON_10 MON_11 MON_12
-	       MON_2 MON_3 MON_4 MON_5 MON_6 MON_7 MON_8 MON_9 NOEXPR NOSTR
-	       PM_STR RADIXCHAR THOUSEP T_FMT T_FMT_AMPM YESEXPR YESSTR));
-
-print constant_types(); # macro defs
-foreach (C_constant ("I18N::Langinfo", 'constant', 'IV', $types, undef, 3, @names) ) {
-    print $_, "\n"; # C constant subs
-}
-print "#### XS Section:\n";
-print XS_constant ("I18N::Langinfo", $types);
-__END__
-   */
-
-  switch (len) {
-  case 3:
-    if (memEQ(name, "ERA", 3)) {
-#ifdef ERA
-      *iv_return = ERA;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  case 5:
-    return constant_5 (aTHX_ name, iv_return);
-    break;
-  case 6:
-    return constant_6 (aTHX_ name, iv_return);
-    break;
-  case 7:
-    return constant_7 (aTHX_ name, iv_return);
-    break;
-  case 8:
-    return constant_8 (aTHX_ name, iv_return);
-    break;
-  case 9:
-    return constant_9 (aTHX_ name, iv_return);
-    break;
-  case 10:
-    /* Names all of length 10.  */
-    /* ALT_DIGITS T_FMT_AMPM */
-    /* Offset 7 gives the best switch position.  */
-    switch (name[7]) {
-    case 'I':
-      if (memEQ(name, "ALT_DIGITS", 10)) {
-      /*                      ^         */
-#ifdef ALT_DIGITS
-        *iv_return = ALT_DIGITS;
-        return PERL_constant_ISIV;
-#else
-        return PERL_constant_NOTDEF;
-#endif
-      }
-      break;
-    case 'M':
-      if (memEQ(name, "T_FMT_AMPM", 10)) {
-      /*                      ^         */
-#ifdef T_FMT_AMPM
-        *iv_return = T_FMT_AMPM;
-        return PERL_constant_ISIV;
-#else
-        return PERL_constant_NOTDEF;
-#endif
-      }
-      break;
-    }
-    break;
-  case 11:
-    if (memEQ(name, "ERA_D_T_FMT", 11)) {
-#ifdef ERA_D_T_FMT
-      *iv_return = ERA_D_T_FMT;
-      return PERL_constant_ISIV;
-#else
-      return PERL_constant_NOTDEF;
-#endif
-    }
-    break;
-  }
-  return PERL_constant_NOTFOUND;
-}
+#include "constants.c"
 
 MODULE = I18N::Langinfo	PACKAGE = I18N::Langinfo
 
 PROTOTYPES: ENABLE
 
-void
-constant(sv)
-    PREINIT:
-#ifdef dXSTARG
-	dXSTARG; /* Faster if we have it.  */
-#else
-	dTARGET;
-#endif
-	STRLEN		len;
-        int		type;
-	IV		iv;
-	/* NV		nv;	Uncomment this if you need to return NVs */
-	/* const char	*pv;	Uncomment this if you need to return PVs */
-    INPUT:
-	SV *		sv;
-        const char *	s = SvPV(sv, len);
-    PPCODE:
-        /* Change this to constant(aTHX_ s, len, &iv, &nv);
-           if you need to return both NVs and IVs */
-	type = constant(aTHX_ s, len, &iv);
-      /* Return 1 or 2 items. First is error message, or undef if no error.
-           Second, if present, is found value */
-        switch (type) {
-        case PERL_constant_NOTFOUND:
-          sv = sv_2mortal(newSVpvf("%s is not a valid I18N::Langinfo macro", s));
-          PUSHs(sv);
-          break;
-        case PERL_constant_NOTDEF:
-          sv = sv_2mortal(newSVpvf(
-	    "Your vendor has not defined I18N::Langinfo macro %s, used", s));
-          PUSHs(sv);
-          break;
-        case PERL_constant_ISIV:
-          EXTEND(SP, 1);
-          PUSHs(&PL_sv_undef);
-          PUSHi(iv);
-          break;
-	/* Uncomment this if you need to return NOs
-        case PERL_constant_ISNO:
-          EXTEND(SP, 1);
-          PUSHs(&PL_sv_undef);
-          PUSHs(&PL_sv_no);
-          break; */
-	/* Uncomment this if you need to return NVs
-        case PERL_constant_ISNV:
-          EXTEND(SP, 1);
-          PUSHs(&PL_sv_undef);
-          PUSHn(nv);
-          break; */
-	/* Uncomment this if you need to return PVs
-        case PERL_constant_ISPV:
-          EXTEND(SP, 1);
-          PUSHs(&PL_sv_undef);
-          PUSHp(pv, strlen(pv));
-          break; */
-	/* Uncomment this if you need to return PVNs
-        case PERL_constant_ISPVN:
-          EXTEND(SP, 1);
-          PUSHs(&PL_sv_undef);
-          PUSHp(pv, iv);
-          break; */
-	/* Uncomment this if you need to return SVs
-        case PERL_constant_ISSV:
-          EXTEND(SP, 1);
-          PUSHs(&PL_sv_undef);
-          PUSHs(sv);
-          break; */
-	/* Uncomment this if you need to return UNDEFs
-        case PERL_constant_ISUNDEF:
-          break; */
-	/* Uncomment this if you need to return UVs
-        case PERL_constant_ISUV:
-          EXTEND(SP, 1);
-          PUSHs(&PL_sv_undef);
-          PUSHu((UV)iv);
-          break; */
-	/* Uncomment this if you need to return YESs
-        case PERL_constant_ISYES:
-          EXTEND(SP, 1);
-          PUSHs(&PL_sv_undef);
-          PUSHs(&PL_sv_yes);
-          break; */
-        default:
-          sv = sv_2mortal(newSVpvf(
-	    "Unexpected return type %d while processing I18N::Langinfo macro %s, used",
-               type, s));
-          PUSHs(sv);
-        }
+INCLUDE: constants.xs
 
 SV*
 langinfo(code)
diff --git a/ext/I18N/Langinfo/Makefile.PL b/ext/I18N/Langinfo/Makefile.PL
index aff6f87107..63137ff90a 100644
--- a/ext/I18N/Langinfo/Makefile.PL
+++ b/ext/I18N/Langinfo/Makefile.PL
@@ -12,6 +12,30 @@ WriteMakefile(
     'DEFINE'		=> '', # e.g., '-DHAVE_SOMETHING'
 	# Insert -I. if you add *.h files later:
     'INC'		=> '', # e.g., '-I/usr/include/other'
+    # Without this the constants xs files are spotted, and cause rules to be
+    # added to delete the similarly named C files, which isn't what we want.
+    XS => {'Langinfo.xs' => 'Langinfo.c'},
+    realclean => {FILES=> 'constants.c constants.xs'},
 	# Un-comment this if you add C files to link with later:
     # 'OBJECT'		=> '$(O_FILES)', # link all the C files too
 );
+if (eval {require ExtUtils::Constant; 1}) {
+  my @names = (qw(ABDAY_1 ABDAY_2 ABDAY_3 ABDAY_4 ABDAY_5 ABDAY_6 ABDAY_7
+                  ABMON_1 ABMON_10 ABMON_11 ABMON_12 ABMON_2 ABMON_3 ABMON_4
+                  ABMON_5 ABMON_6 ABMON_7 ABMON_8 ABMON_9 ALT_DIGITS AM_STR
+                  CODESET CRNCYSTR DAY_1 DAY_2 DAY_3 DAY_4 DAY_5 DAY_6 DAY_7
+                  D_FMT D_T_FMT ERA ERA_D_FMT ERA_D_T_FMT ERA_T_FMT MON_1
+                  MON_10 MON_11 MON_12 MON_2 MON_3 MON_4 MON_5 MON_6 MON_7
+                  MON_8 MON_9 NOEXPR NOSTR PM_STR RADIXCHAR THOUSEP T_FMT
+                  T_FMT_AMPM YESEXPR YESSTR));
+  ExtUtils::Constant::WriteConstants(
+                                     NAME => 'I18N::Langinfo',
+                                     NAMES => \@names,
+                                    );
+} else {
+  use File::Copy;
+  copy ('fallback.c', 'constants.c')
+    or die "Can't copy fallback.c to constants.c: $!";
+  copy ('fallback.xs', 'constants.xs')
+    or die "Can't copy fallback.xs to constants.xs: $!";
+}
diff --git a/ext/I18N/Langinfo/fallback.c b/ext/I18N/Langinfo/fallback.c
new file mode 100644
index 0000000000..538a9f753c
--- /dev/null
+++ b/ext/I18N/Langinfo/fallback.c
@@ -0,0 +1,724 @@
+#define PERL_constant_NOTFOUND	1
+#define PERL_constant_NOTDEF	2
+#define PERL_constant_ISIV	3
+#define PERL_constant_ISNO	4
+#define PERL_constant_ISNV	5
+#define PERL_constant_ISPV	6
+#define PERL_constant_ISPVN	7
+#define PERL_constant_ISSV	8
+#define PERL_constant_ISUNDEF	9
+#define PERL_constant_ISUV	10
+#define PERL_constant_ISYES	11
+
+#ifndef NVTYPE
+typedef double NV; /* 5.6 and later define NVTYPE, and typedef NV to it.  */
+#endif
+
+static int
+constant_5 (pTHX_ const char *name, IV *iv_return) {
+  /* When generated this function returned values for the list of names given
+     here.  However, subsequent manual editing may have added or removed some.
+     DAY_1 DAY_2 DAY_3 DAY_4 DAY_5 DAY_6 DAY_7 D_FMT MON_1 MON_2 MON_3 MON_4
+     MON_5 MON_6 MON_7 MON_8 MON_9 NOSTR T_FMT */
+  /* Offset 4 gives the best switch position.  */
+  switch (name[4]) {
+  case '1':
+    if (memEQ(name, "DAY_1", 5)) {
+    /*                   ^      */
+#ifdef DAY_1
+      *iv_return = DAY_1;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_1", 5)) {
+    /*                   ^      */
+#ifdef MON_1
+      *iv_return = MON_1;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '2':
+    if (memEQ(name, "DAY_2", 5)) {
+    /*                   ^      */
+#ifdef DAY_2
+      *iv_return = DAY_2;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_2", 5)) {
+    /*                   ^      */
+#ifdef MON_2
+      *iv_return = MON_2;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '3':
+    if (memEQ(name, "DAY_3", 5)) {
+    /*                   ^      */
+#ifdef DAY_3
+      *iv_return = DAY_3;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_3", 5)) {
+    /*                   ^      */
+#ifdef MON_3
+      *iv_return = MON_3;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '4':
+    if (memEQ(name, "DAY_4", 5)) {
+    /*                   ^      */
+#ifdef DAY_4
+      *iv_return = DAY_4;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_4", 5)) {
+    /*                   ^      */
+#ifdef MON_4
+      *iv_return = MON_4;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '5':
+    if (memEQ(name, "DAY_5", 5)) {
+    /*                   ^      */
+#ifdef DAY_5
+      *iv_return = DAY_5;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_5", 5)) {
+    /*                   ^      */
+#ifdef MON_5
+      *iv_return = MON_5;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '6':
+    if (memEQ(name, "DAY_6", 5)) {
+    /*                   ^      */
+#ifdef DAY_6
+      *iv_return = DAY_6;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_6", 5)) {
+    /*                   ^      */
+#ifdef MON_6
+      *iv_return = MON_6;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '7':
+    if (memEQ(name, "DAY_7", 5)) {
+    /*                   ^      */
+#ifdef DAY_7
+      *iv_return = DAY_7;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_7", 5)) {
+    /*                   ^      */
+#ifdef MON_7
+      *iv_return = MON_7;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '8':
+    if (memEQ(name, "MON_8", 5)) {
+    /*                   ^      */
+#ifdef MON_8
+      *iv_return = MON_8;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '9':
+    if (memEQ(name, "MON_9", 5)) {
+    /*                   ^      */
+#ifdef MON_9
+      *iv_return = MON_9;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'R':
+    if (memEQ(name, "NOSTR", 5)) {
+    /*                   ^      */
+#ifdef NOSTR
+      *iv_return = NOSTR;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'T':
+    if (memEQ(name, "D_FMT", 5)) {
+    /*                   ^      */
+#ifdef D_FMT
+      *iv_return = D_FMT;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "T_FMT", 5)) {
+    /*                   ^      */
+#ifdef T_FMT
+      *iv_return = T_FMT;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  }
+  return PERL_constant_NOTFOUND;
+}
+
+static int
+constant_6 (pTHX_ const char *name, IV *iv_return) {
+  /* When generated this function returned values for the list of names given
+     here.  However, subsequent manual editing may have added or removed some.
+     AM_STR MON_10 MON_11 MON_12 NOEXPR PM_STR YESSTR */
+  /* Offset 0 gives the best switch position.  */
+  switch (name[0]) {
+  case 'A':
+    if (memEQ(name, "AM_STR", 6)) {
+    /*               ^           */
+#ifdef AM_STR
+      *iv_return = AM_STR;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'M':
+    if (memEQ(name, "MON_10", 6)) {
+    /*               ^           */
+#ifdef MON_10
+      *iv_return = MON_10;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_11", 6)) {
+    /*               ^           */
+#ifdef MON_11
+      *iv_return = MON_11;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "MON_12", 6)) {
+    /*               ^           */
+#ifdef MON_12
+      *iv_return = MON_12;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'N':
+    if (memEQ(name, "NOEXPR", 6)) {
+    /*               ^           */
+#ifdef NOEXPR
+      *iv_return = NOEXPR;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'P':
+    if (memEQ(name, "PM_STR", 6)) {
+    /*               ^           */
+#ifdef PM_STR
+      *iv_return = PM_STR;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'Y':
+    if (memEQ(name, "YESSTR", 6)) {
+    /*               ^           */
+#ifdef YESSTR
+      *iv_return = YESSTR;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  }
+  return PERL_constant_NOTFOUND;
+}
+
+static int
+constant_7 (pTHX_ const char *name, IV *iv_return) {
+  /* When generated this function returned values for the list of names given
+     here.  However, subsequent manual editing may have added or removed some.
+     ABDAY_1 ABDAY_2 ABDAY_3 ABDAY_4 ABDAY_5 ABDAY_6 ABDAY_7 ABMON_1 ABMON_2
+     ABMON_3 ABMON_4 ABMON_5 ABMON_6 ABMON_7 ABMON_8 ABMON_9 CODESET D_T_FMT
+     THOUSEP YESEXPR */
+  /* Offset 6 gives the best switch position.  */
+  switch (name[6]) {
+  case '1':
+    if (memEQ(name, "ABDAY_1", 7)) {
+    /*                     ^      */
+#ifdef ABDAY_1
+      *iv_return = ABDAY_1;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "ABMON_1", 7)) {
+    /*                     ^      */
+#ifdef ABMON_1
+      *iv_return = ABMON_1;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '2':
+    if (memEQ(name, "ABDAY_2", 7)) {
+    /*                     ^      */
+#ifdef ABDAY_2
+      *iv_return = ABDAY_2;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "ABMON_2", 7)) {
+    /*                     ^      */
+#ifdef ABMON_2
+      *iv_return = ABMON_2;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '3':
+    if (memEQ(name, "ABDAY_3", 7)) {
+    /*                     ^      */
+#ifdef ABDAY_3
+      *iv_return = ABDAY_3;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "ABMON_3", 7)) {
+    /*                     ^      */
+#ifdef ABMON_3
+      *iv_return = ABMON_3;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '4':
+    if (memEQ(name, "ABDAY_4", 7)) {
+    /*                     ^      */
+#ifdef ABDAY_4
+      *iv_return = ABDAY_4;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "ABMON_4", 7)) {
+    /*                     ^      */
+#ifdef ABMON_4
+      *iv_return = ABMON_4;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '5':
+    if (memEQ(name, "ABDAY_5", 7)) {
+    /*                     ^      */
+#ifdef ABDAY_5
+      *iv_return = ABDAY_5;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "ABMON_5", 7)) {
+    /*                     ^      */
+#ifdef ABMON_5
+      *iv_return = ABMON_5;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '6':
+    if (memEQ(name, "ABDAY_6", 7)) {
+    /*                     ^      */
+#ifdef ABDAY_6
+      *iv_return = ABDAY_6;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "ABMON_6", 7)) {
+    /*                     ^      */
+#ifdef ABMON_6
+      *iv_return = ABMON_6;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '7':
+    if (memEQ(name, "ABDAY_7", 7)) {
+    /*                     ^      */
+#ifdef ABDAY_7
+      *iv_return = ABDAY_7;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "ABMON_7", 7)) {
+    /*                     ^      */
+#ifdef ABMON_7
+      *iv_return = ABMON_7;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '8':
+    if (memEQ(name, "ABMON_8", 7)) {
+    /*                     ^      */
+#ifdef ABMON_8
+      *iv_return = ABMON_8;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '9':
+    if (memEQ(name, "ABMON_9", 7)) {
+    /*                     ^      */
+#ifdef ABMON_9
+      *iv_return = ABMON_9;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'P':
+    if (memEQ(name, "THOUSEP", 7)) {
+    /*                     ^      */
+#ifdef THOUSEP
+      *iv_return = THOUSEP;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'R':
+    if (memEQ(name, "YESEXPR", 7)) {
+    /*                     ^      */
+#ifdef YESEXPR
+      *iv_return = YESEXPR;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'T':
+    if (memEQ(name, "CODESET", 7)) {
+    /*                     ^      */
+#ifdef CODESET
+      *iv_return = CODESET;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    if (memEQ(name, "D_T_FMT", 7)) {
+    /*                     ^      */
+#ifdef D_T_FMT
+      *iv_return = D_T_FMT;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  }
+  return PERL_constant_NOTFOUND;
+}
+
+static int
+constant_8 (pTHX_ const char *name, IV *iv_return) {
+  /* When generated this function returned values for the list of names given
+     here.  However, subsequent manual editing may have added or removed some.
+     ABMON_10 ABMON_11 ABMON_12 CRNCYSTR */
+  /* Offset 7 gives the best switch position.  */
+  switch (name[7]) {
+  case '0':
+    if (memEQ(name, "ABMON_10", 8)) {
+    /*                      ^      */
+#ifdef ABMON_10
+      *iv_return = ABMON_10;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '1':
+    if (memEQ(name, "ABMON_11", 8)) {
+    /*                      ^      */
+#ifdef ABMON_11
+      *iv_return = ABMON_11;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case '2':
+    if (memEQ(name, "ABMON_12", 8)) {
+    /*                      ^      */
+#ifdef ABMON_12
+      *iv_return = ABMON_12;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'R':
+    if (memEQ(name, "CRNCYSTR", 8)) {
+    /*                      ^      */
+#ifdef CRNCYSTR
+      *iv_return = CRNCYSTR;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  }
+  return PERL_constant_NOTFOUND;
+}
+
+static int
+constant_9 (pTHX_ const char *name, IV *iv_return) {
+  /* When generated this function returned values for the list of names given
+     here.  However, subsequent manual editing may have added or removed some.
+     ERA_D_FMT ERA_T_FMT RADIXCHAR */
+  /* Offset 4 gives the best switch position.  */
+  switch (name[4]) {
+  case 'D':
+    if (memEQ(name, "ERA_D_FMT", 9)) {
+    /*                   ^          */
+#ifdef ERA_D_FMT
+      *iv_return = ERA_D_FMT;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'T':
+    if (memEQ(name, "ERA_T_FMT", 9)) {
+    /*                   ^          */
+#ifdef ERA_T_FMT
+      *iv_return = ERA_T_FMT;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 'X':
+    if (memEQ(name, "RADIXCHAR", 9)) {
+    /*                   ^          */
+#ifdef RADIXCHAR
+      *iv_return = RADIXCHAR;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  }
+  return PERL_constant_NOTFOUND;
+}
+
+static int
+constant (pTHX_ const char *name, STRLEN len, IV *iv_return) {
+  /* Initially switch on the length of the name.  */
+  /* When generated this function returned values for the list of names given
+     in this section of perl code.  Rather than manually editing these functions
+     to add or remove constants, which would result in this comment and section
+     of code becoming inaccurate, we recommend that you edit this section of
+     code, and use it to regenerate a new set of constant functions which you
+     then use to replace the originals.
+
+     Regenerate these constant functions by feeding this entire source file to
+     perl -x
+
+#!../../../miniperl -w
+use ExtUtils::Constant qw (constant_types C_constant XS_constant);
+
+my $types = {map {($_, 1)} qw(IV)};
+my @names = (qw(ABDAY_1 ABDAY_2 ABDAY_3 ABDAY_4 ABDAY_5 ABDAY_6 ABDAY_7 ABMON_1
+	       ABMON_10 ABMON_11 ABMON_12 ABMON_2 ABMON_3 ABMON_4 ABMON_5
+	       ABMON_6 ABMON_7 ABMON_8 ABMON_9 ALT_DIGITS AM_STR CODESET
+	       CRNCYSTR DAY_1 DAY_2 DAY_3 DAY_4 DAY_5 DAY_6 DAY_7 D_FMT D_T_FMT
+	       ERA ERA_D_FMT ERA_D_T_FMT ERA_T_FMT MON_1 MON_10 MON_11 MON_12
+	       MON_2 MON_3 MON_4 MON_5 MON_6 MON_7 MON_8 MON_9 NOEXPR NOSTR
+	       PM_STR RADIXCHAR THOUSEP T_FMT T_FMT_AMPM YESEXPR YESSTR));
+
+print constant_types(); # macro defs
+foreach (C_constant ("I18N::Langinfo", 'constant', 'IV', $types, undef, 3, @names) ) {
+    print $_, "\n"; # C constant subs
+}
+print "#### XS Section:\n";
+print XS_constant ("I18N::Langinfo", $types);
+__END__
+   */
+
+  switch (len) {
+  case 3:
+    if (memEQ(name, "ERA", 3)) {
+#ifdef ERA
+      *iv_return = ERA;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  case 5:
+    return constant_5 (aTHX_ name, iv_return);
+    break;
+  case 6:
+    return constant_6 (aTHX_ name, iv_return);
+    break;
+  case 7:
+    return constant_7 (aTHX_ name, iv_return);
+    break;
+  case 8:
+    return constant_8 (aTHX_ name, iv_return);
+    break;
+  case 9:
+    return constant_9 (aTHX_ name, iv_return);
+    break;
+  case 10:
+    /* Names all of length 10.  */
+    /* ALT_DIGITS T_FMT_AMPM */
+    /* Offset 7 gives the best switch position.  */
+    switch (name[7]) {
+    case 'I':
+      if (memEQ(name, "ALT_DIGITS", 10)) {
+      /*                      ^         */
+#ifdef ALT_DIGITS
+        *iv_return = ALT_DIGITS;
+        return PERL_constant_ISIV;
+#else
+        return PERL_constant_NOTDEF;
+#endif
+      }
+      break;
+    case 'M':
+      if (memEQ(name, "T_FMT_AMPM", 10)) {
+      /*                      ^         */
+#ifdef T_FMT_AMPM
+        *iv_return = T_FMT_AMPM;
+        return PERL_constant_ISIV;
+#else
+        return PERL_constant_NOTDEF;
+#endif
+      }
+      break;
+    }
+    break;
+  case 11:
+    if (memEQ(name, "ERA_D_T_FMT", 11)) {
+#ifdef ERA_D_T_FMT
+      *iv_return = ERA_D_T_FMT;
+      return PERL_constant_ISIV;
+#else
+      return PERL_constant_NOTDEF;
+#endif
+    }
+    break;
+  }
+  return PERL_constant_NOTFOUND;
+}
+
diff --git a/ext/I18N/Langinfo/fallback.xs b/ext/I18N/Langinfo/fallback.xs
new file mode 100644
index 0000000000..16ae6e803d
--- /dev/null
+++ b/ext/I18N/Langinfo/fallback.xs
@@ -0,0 +1,88 @@
+void
+constant(sv)
+    PREINIT:
+#ifdef dXSTARG
+	dXSTARG; /* Faster if we have it.  */
+#else
+	dTARGET;
+#endif
+	STRLEN		len;
+        int		type;
+	IV		iv;
+	/* NV		nv;	Uncomment this if you need to return NVs */
+	/* const char	*pv;	Uncomment this if you need to return PVs */
+    INPUT:
+	SV *		sv;
+        const char *	s = SvPV(sv, len);
+    PPCODE:
+        /* Change this to constant(aTHX_ s, len, &iv, &nv);
+           if you need to return both NVs and IVs */
+	type = constant(aTHX_ s, len, &iv);
+      /* Return 1 or 2 items. First is error message, or undef if no error.
+           Second, if present, is found value */
+        switch (type) {
+        case PERL_constant_NOTFOUND:
+          sv = sv_2mortal(newSVpvf("%s is not a valid I18N::Langinfo macro", s));
+          PUSHs(sv);
+          break;
+        case PERL_constant_NOTDEF:
+          sv = sv_2mortal(newSVpvf(
+	    "Your vendor has not defined I18N::Langinfo macro %s, used", s));
+          PUSHs(sv);
+          break;
+        case PERL_constant_ISIV:
+          EXTEND(SP, 1);
+          PUSHs(&PL_sv_undef);
+          PUSHi(iv);
+          break;
+	/* Uncomment this if you need to return NOs
+        case PERL_constant_ISNO:
+          EXTEND(SP, 1);
+          PUSHs(&PL_sv_undef);
+          PUSHs(&PL_sv_no);
+          break; */
+	/* Uncomment this if you need to return NVs
+        case PERL_constant_ISNV:
+          EXTEND(SP, 1);
+          PUSHs(&PL_sv_undef);
+          PUSHn(nv);
+          break; */
+	/* Uncomment this if you need to return PVs
+        case PERL_constant_ISPV:
+          EXTEND(SP, 1);
+          PUSHs(&PL_sv_undef);
+          PUSHp(pv, strlen(pv));
+          break; */
+	/* Uncomment this if you need to return PVNs
+        case PERL_constant_ISPVN:
+          EXTEND(SP, 1);
+          PUSHs(&PL_sv_undef);
+          PUSHp(pv, iv);
+          break; */
+	/* Uncomment this if you need to return SVs
+        case PERL_constant_ISSV:
+          EXTEND(SP, 1);
+          PUSHs(&PL_sv_undef);
+          PUSHs(sv);
+          break; */
+	/* Uncomment this if you need to return UNDEFs
+        case PERL_constant_ISUNDEF:
+          break; */
+	/* Uncomment this if you need to return UVs
+        case PERL_constant_ISUV:
+          EXTEND(SP, 1);
+          PUSHs(&PL_sv_undef);
+          PUSHu((UV)iv);
+          break; */
+	/* Uncomment this if you need to return YESs
+        case PERL_constant_ISYES:
+          EXTEND(SP, 1);
+          PUSHs(&PL_sv_undef);
+          PUSHs(&PL_sv_yes);
+          break; */
+        default:
+          sv = sv_2mortal(newSVpvf(
+	    "Unexpected return type %d while processing I18N::Langinfo macro %s, used",
+               type, s));
+          PUSHs(sv);
+        }