One more IVUV tweak from Nicholas Clark.

p4raw-id: //depot/perl@8139

diff --git a/sv.c b/sv.c
index 3b3351c..1dafbf6 100644 (file)
--- a/sv.c
+++ b/sv.c
@@ -2067,17 +2067,32 @@ Perl_sv_2uv(pTHX_ register SV *sv)
        } else {
 #ifdef HAS_STRTOUL
            UV u;
+           char *num_begin = SvPVX(sv);
            int save_errno = errno;
+           
+           /* seems that strtoul taking numbers that start with - is
+              implementation dependant, and can't be relied upon.  */
+           if (numtype & IS_NUMBER_NEG) {
+               /* Not totally defensive. assumine that looks_like_num
+                  didn't lie about a - sign */
+               while (isSPACE(*num_begin))
+                   num_begin++;
+               if (*num_begin == '-')
+                   num_begin++;
+           }
+    
            /* Is it an integer that we could convert with strtoul?
               So try it, and if it doesn't set errno then it's pukka.
               This should be faster than going atof and then thinking.  */
            if (((numtype & (IS_NUMBER_TO_INT_BY_STRTOL | IS_NUMBER_NOT_INT))
                 == IS_NUMBER_TO_INT_BY_STRTOL)
                && ((errno = 0), 1) /* always true */
-               && ((u = Strtoul(SvPVX(sv), Null(char**), 10)), 1) /* ditto */
+               && ((u = Strtoul(num_begin, Null(char**), 10)), 1) /* ditto */
                && (errno == 0)
-               /* If known to be negative, check it didn't undeflow IV */
-               && ((numtype & IS_NUMBER_NEG) ? ((IV)u <= 0) : 1)) {
+               /* If known to be negative, check it didn't undeflow IV 
+                  XXX possibly we should put more negative values as NVs
+                  direct rather than go via atof below */
+               && ((numtype & IS_NUMBER_NEG) ? (u <= (UV)IV_MIN) : 1)) {
                errno = save_errno;
 
                if (SvTYPE(sv) < SVt_PVIV)
@@ -2086,14 +2101,9 @@ Perl_sv_2uv(pTHX_ register SV *sv)
 
                /* If it's negative must use IV.
                   IV-over-UV optimisation */
-               if (numtype & IS_NUMBER_NEG || u <= (UV) IV_MAX) {
-                   /* strtoul is defined to return negated value if the
-                      number starts with a minus sign. Assuming 2s
-                      complement, this value will be in range for a negative
-                      IV if casting the bit pattern to IV doesn't produce
-                      a positive value. Allow -0 by checking it's <= 0
-                      hence (numtype & IS_NUMBER_NEG) test above
-                   */
+               if (numtype & IS_NUMBER_NEG) {
+                   SvIVX(sv) = -(IV)u;
+               } else if (u <= (UV) IV_MAX) {
                    SvIVX(sv) = (IV)u;
                } else {
                    /* it didn't overflow, and it was positive. */