Revert SvPVX() to allow lvalue usage, but also add a

MUTABLE_SV() check. Use SvPVX_const() instead of SvPVX()
where only a const SV* is available. Also fix two falsely
consted pointers in Perl_sv_2pv_flags().

p4raw-id: //depot/perl@34770

1 files changed, 1 insertions, 1 deletions

diff --git a/regexec.c b/regexec.c
index 363e205589..025d1592f4 100644
--- a/regexec.c
+++ b/regexec.c
@@ -2590,7 +2590,7 @@ S_debug_start_match(pTHX_ const REGEXP *prog, const bool do_utf8,
             reginitcolors();    
     {
         RE_PV_QUOTED_DECL(s0, utf8_pat, PERL_DEBUG_PAD_ZERO(0), 
-            RX_PRECOMP(prog), RX_PRELEN(prog), 60);   
+            RX_PRECOMP_const(prog), RX_PRELEN(prog), 60);   
         
         RE_PV_QUOTED_DECL(s1, do_utf8, PERL_DEBUG_PAD_ZERO(1), 
             start, end - start, 60);