Assert that SV type has magic member when reading/writing.

Will catch buggy code.

p4raw-id: //depot/perl@22934

diff --git a/sv.c b/sv.c
index fe1d406..57ca682 100644 (file)
--- a/sv.c
+++ b/sv.c
@@ -1869,6 +1869,9 @@ Perl_sv_upgrade(pTHX_ register SV *sv, U32 mt)
        Perl_croak(aTHX_ "Can't upgrade that kind of scalar");
     }
 
+    SvFLAGS(sv) &= ~SVTYPEMASK;
+    SvFLAGS(sv) |= mt;
+
     switch (mt) {
     case SVt_NULL:
        Perl_croak(aTHX_ "Can't upgrade to undef");
@@ -2031,8 +2034,6 @@ Perl_sv_upgrade(pTHX_ register SV *sv, U32 mt)
        IoPAGE_LEN(sv)  = 60;
        break;
     }
-    SvFLAGS(sv) &= ~SVTYPEMASK;
-    SvFLAGS(sv) |= mt;
     return TRUE;
 }
 

diff --git a/sv.h b/sv.h
index 4edd87f..bc03bb8 100644 (file)
--- a/sv.h
+++ b/sv.h
@@ -739,8 +739,14 @@ and leaves the UTF-8 status as it was.
 #define SvLENx(sv) SvLEN(sv)
 #define SvEND(sv)(((XPV*)  SvANY(sv))->xpv_pv + ((XPV*)SvANY(sv))->xpv_cur)
 #define SvENDx(sv) ((PL_Sv = (sv)), SvEND(PL_Sv))
+
+#ifdef DEBUGGING
+#define SvMAGIC(sv)    ((assert(SvTYPE(sv) >= SVt_PVMG)), ((XPVMG*)  SvANY(sv))->xmg_magic)
+#define SvSTASH(sv)    ((XPVMG*)  SvANY(sv))->xmg_stash
+#else
 #define SvMAGIC(sv)    ((XPVMG*)  SvANY(sv))->xmg_magic
 #define SvSTASH(sv)    ((XPVMG*)  SvANY(sv))->xmg_stash
+#endif
 
 /* Ask a scalar nicely to try to become an IV, if possible.
    Not guaranteed to stay returning void */