Integrate mainline to perlio branch

p4raw-id: //depot/perlio@7486

diff --cc iperlsys.h
index 9357e0e,6844801..caca9df
--- 1/iperlsys.h
--- 2/iperlsys.h
+++ b/iperlsys.h
@@@ -185,14 -185,20 +185,20 @@@ struct IPerlStdIOInf
  };
  
  #ifdef USE_STDIO_PTR
 -#  define PerlIO_has_cntptr(f)                1       
 +#  define PerlIO_has_cntptr(f)                1
- #  ifdef STDIO_CNT_LVALUE
- #    define PerlIO_canset_cnt(f)      1
- #    ifdef STDIO_PTR_LVALUE
+ #  ifdef STDIO_PTR_LVALUE
+ #    ifdef  STDIO_CNT_LVALUE
 -#      define PerlIO_canset_cnt(f)    1      
++#      define PerlIO_canset_cnt(f)    1
+ #      ifdef STDIO_PTR_LVAL_NOCHANGE_CNT
 -#        define PerlIO_fast_gets(f)   1        
++#        define PerlIO_fast_gets(f)   1
+ #      endif
+ #    else /* STDIO_CNT_LVALUE */
 -#      define PerlIO_canset_cnt(f)    0      
++#      define PerlIO_canset_cnt(f)    0
+ #    endif
+ #  else /* STDIO_PTR_LVALUE */
+ #    ifdef STDIO_PTR_LVAL_SETS_CNT
 -#      define PerlIO_fast_gets(f)     1        
 +#      define PerlIO_fast_gets(f)     1
  #    endif
- #  else
- #    define PerlIO_canset_cnt(f)      0
  #  endif
  #else  /* USE_STDIO_PTR */
  #  define PerlIO_has_cntptr(f)                0