scalars don't have a length. Do you mean the string contained within a scalar? I think 64-bit lengths on builds with 64-bit IVs. However, I recently heard many builtins (index? substr?) use 32-bit indexes.

Update: Found this: 

/* Size_t:
 *    This symbol holds the type used to declare length parameters
 *    for string functions.  It is usually size_t, but may be
 *    unsigned long, int, etc.  It may be necessary to include
 *    <sys/types.h> to get any typedef'ed information.
 */
#define Size_t size_t     /* length paramater for string functions */

#define MEM_SIZE Size_t

typedef MEM_SIZE STRLEN;

    STRLEN      xpv_cur;        /* length of svu_pv as a C string */
    STRLEN      xpv_len         /* allocated size */

[download]

I have no idea what that means, but it appears to be configurable somehow since Size_t is defined in a file called "uconfig.h".

In reply to Re: PV limits on 64-bit perls? by ikegami
in thread PV limits on 64-bit perls? by BrowserUk

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