Add a macro PERL_DEBUG_COW, for aggressive compile time tests of

Copy-On-Write related source changes.
Fix the problem this revealed.

p4raw-id: //depot/perl@24201

diff --git a/sv.c b/sv.c
index 452dd9c..102a000 100644 (file)
--- a/sv.c
+++ b/sv.c
@@ -7518,7 +7518,7 @@ Perl_sv_dec(pTHX_ register SV *sv)
     if (!(flags & SVp_POK)) {
        if ((flags & SVTYPEMASK) < SVt_PVNV)
            sv_upgrade(sv, SVt_NV);
-       SvNVX(sv) = -1.0;
+       SvNV_set(sv, 1.0);
        (void)SvNOK_only(sv);
        return;
     }

diff --git a/sv.h b/sv.h
index 09dae3f..5e0c45e 100644 (file)
--- a/sv.h
+++ b/sv.h
@@ -737,17 +737,22 @@ in gv.h: */
 #define SvRVx(sv) SvRV(sv)
 
 #define SvIVX(sv) ((XPVIV*)  SvANY(sv))->xiv_iv
-#define SvIVXx(sv) SvIVX(sv)
 #define SvUVX(sv) ((XPVUV*)  SvANY(sv))->xuv_uv
-#define SvUVXx(sv) SvUVX(sv)
+#ifdef PERL_DEBUG_COW
+#define SvNVX(sv)  (0.0 + ((XPVNV*)SvANY(sv))->xnv_nv)
+#else
 #define SvNVX(sv)  ((XPVNV*)SvANY(sv))->xnv_nv
-#define SvNVXx(sv) SvNVX(sv)
+#endif
 #define SvPVX(sv)  ((XPV*)  SvANY(sv))->xpv_pv
-#define SvPVXx(sv) SvPVX(sv)
 #define SvCUR(sv) ((XPV*)  SvANY(sv))->xpv_cur
 #define SvLEN(sv) ((XPV*)  SvANY(sv))->xpv_len
-#define SvLENx(sv) SvLEN(sv)
 #define SvEND(sv)(((XPV*)  SvANY(sv))->xpv_pv + ((XPV*)SvANY(sv))->xpv_cur)
+
+#define SvIVXx(sv) SvIVX(sv)
+#define SvUVXx(sv) SvUVX(sv)
+#define SvNVXx(sv) SvNVX(sv)
+#define SvPVXx(sv) SvPVX(sv)
+#define SvLENx(sv) SvLEN(sv)
 #define SvENDx(sv) ((PL_Sv = (sv)), SvEND(PL_Sv))
 
 #ifdef DEBUGGING
@@ -769,7 +774,7 @@ in gv.h: */
                (SvIVX(sv) = (val)); } STMT_END
 #define SvNV_set(sv, val) \
        STMT_START { assert(SvTYPE(sv) == SVt_NV || SvTYPE(sv) >= SVt_PVNV); \
-               (SvNVX(sv) = (val)); } STMT_END
+               (((XPVNV*)SvANY(sv))->xnv_nv = (val)); } STMT_END
 #define SvPV_set(sv, val) \
        STMT_START { assert(SvTYPE(sv) >= SVt_PV); \
                (SvPVX(sv) = (val)); } STMT_END