[perl #87708] use integer; $tied <=> $tied

This is just part of #87708.

This fixes <=> under ‘use integer’ when the same tied scalar is used
for both operands and returns two different values. Before this com-
mit, get-magic would be called only once and the same value used. In
5.12.x, the operands would be reversed.

1 files changed, 5 insertions, 0 deletions

diff --git a/pp.h b/pp.h
index eef6a0b806..e676e045b5 100644
--- a/pp.h
+++ b/pp.h
@@ -380,6 +380,11 @@ Does not use C<TARG>.  See also C<XPUSHu>, C<mPUSHu> and C<PUSHu>.
 #define dPOPTOPiirl_ul_nomg dPOPXiirl_ul_nomg(TOP)
 #define dPOPTOPiirl_nomg \
     IV right = SvIV_nomg(TOPs); IV left = (sp--, SvIV_nomg(TOPs))
+#ifdef PERL_CORE
+# define dPOPTOPiirl_halfmg \
+    IV left  = SvIV_nomg(TOPm1s); \
+    IV right = (sp--, TOPp1s == TOPs ? SvIV(TOPs) : SvIV_nomg(TOPp1s))
+#endif
 
 #define RETPUSHYES	RETURNX(PUSHs(&PL_sv_yes))
 #define RETPUSHNO	RETURNX(PUSHs(&PL_sv_no))