Integrate with Sarathy.

p4raw-id: //depot/cfgperl@6026

diff --combined sv.c
index c885bb2,7f7c9a6..2d075eb
--- 1/sv.c
--- 2/sv.c
+++ b/sv.c
@@@ -1359,7 -1359,6 +1359,7 @@@ S_not_a_number(pTHX_ SV *sv
  #define IS_NUMBER_TO_INT_BY_ATOF 0x02 /* atol() may be != atof() */
  #define IS_NUMBER_NOT_IV       0x04 /* (IV)atof() may be != atof() */
  #define IS_NUMBER_NEG          0x08 /* not good to cache UV */
 +#define IS_NUMBER_INFINITY     0x10 /* this is big */
  
  /* Actually, ISO C leaves conversion of UV to IV undefined, but
     until proven guilty, assume that things are not that bad... */
@@@ -1814,7 -1813,6 +1814,7 @@@ S_asUV(pTHX_ SV *sv
   * IS_NUMBER_TO_INT_BY_ATOL                           123
   * IS_NUMBER_TO_INT_BY_ATOL | IS_NUMBER_NOT_IV                123.1
   * IS_NUMBER_TO_INT_BY_ATOF | IS_NUMBER_NOT_IV                123e0
 + * IS_NUMBER_INFINITY
   * with a possible addition of IS_NUMBER_NEG.
   */
  
@@@ -1835,7 -1833,6 +1835,7 @@@ Perl_looks_like_number(pTHX_ SV *sv
      register char *sbegin;
      register char *nbegin;
      I32 numtype = 0;
 +    I32 sawinf  = 0;
      STRLEN len;
  
      if (SvPOK(sv)) {
@@@ -1865,7 -1862,7 +1865,7 @@@
       * (int)atof().
       */
  
 -    /* next must be digit or the radix separator */
 +    /* next must be digit or the radix separator or beginning of infinity */
      if (isDIGIT(*s)) {
          do {
            s++;
@@@ -1903,38 -1900,23 +1903,38 @@@
          else
            return 0;
      }
 +    else if (*s == 'I' || *s == 'i') {
 +      s++; if (*s != 'N' && *s != 'n') return 0;
 +      s++; if (*s != 'F' && *s != 'f') return 0;
 +      s++; if (*s == 'I' || *s == 'i') {
 +          s++; if (*s != 'N' && *s != 'n') return 0;
 +          s++; if (*s != 'I' && *s != 'i') return 0;
 +          s++; if (*s != 'T' && *s != 't') return 0;
 +          s++; if (*s != 'Y' && *s != 'y') return 0;
 +      }
 +      sawinf = 1;
 +    }
      else
          return 0;
  
 -    /* we can have an optional exponent part */
 -    if (*s == 'e' || *s == 'E') {
 -      numtype &= ~IS_NUMBER_NEG;
 -      numtype |= IS_NUMBER_TO_INT_BY_ATOF | IS_NUMBER_NOT_IV;
 -      s++;
 -      if (*s == '+' || *s == '-')
 +    if (sawinf)
 +      numtype = IS_NUMBER_INFINITY;
 +    else {
 +      /* we can have an optional exponent part */
 +      if (*s == 'e' || *s == 'E') {
 +          numtype &= ~IS_NUMBER_NEG;
 +          numtype |= IS_NUMBER_TO_INT_BY_ATOF | IS_NUMBER_NOT_IV;
            s++;
 -        if (isDIGIT(*s)) {
 -            do {
 -                s++;
 -            } while (isDIGIT(*s));
 -        }
 -        else
 -            return 0;
 +          if (*s == '+' || *s == '-')
 +              s++;
 +          if (isDIGIT(*s)) {
 +              do {
 +                  s++;
 +              } while (isDIGIT(*s));
 +          }
 +          else
 +              return 0;
 +      }
      }
      while (isSPACE(*s))
        s++;
@@@ -7888,6 -7870,7 +7888,7 @@@ perl_clone_using(PerlInterpreter *proto
      }
      else {
        init_stacks();
+       ENTER;                  /* perl_destruct() wants to LEAVE; */
      }
  
      PL_start_env      = proto_perl->Tstart_env;       /* XXXXXX */