* What's new since version 0.5.12?

- When running in -p4 (compile-only) mode, the compiled .ko file name
  is printed on standard output.

- An array element with a null value such as zero or an empty string
  is now preserved, and will show up in a "foreach" loop or "in" test.
  To delete such an element, the scripts needs to use an explicit
  "delete array[idx]" statement rather than something like "array[idx]=0".

- The new "-P" option controls whether prologue searching heuristics
  will be activated for function probes.  This was needed to get correct
  debugging information (dwarf location list) data for $target variables.
  Modern compilers (gcc 4.1+) tend not to need this heuristic, so it is
  no longer default.  A new configure flag (--enable-prologues) restores
  it as a default setting, and is appropriate for older compilers (gcc 3.*).

- Each systemtap module prints a one-line message to the kernel informational
  log when it starts.  This line identifies the translator version, base
  address of the probe module, a broken-down memory consumption estimate, and
  the total number of probes.  This is meant as a debugging / auditing aid.


* What's new since version 0.5.10?

- Offline processing of debugging information, enabling general
  cross-compilation of probe scripts to remote hosts, without
  requiring identical module/memory layout.  This slows down
  compilation/translation somewhat.

- Kernel symbol table data is loaded by staprun at startup time
  rather than compiled into the module.

- Support the "limit" keyword for foreach iterations:
    foreach ([x,y] in ary limit 5) { ... }
  This implicitly exits after the fifth iteration.  It also enables
  more efficient key/value sorting.

- Support the "maxactive" keyword for return probes:
    probe kernel.function("sdfsdf").maxactive(848) { ... }
  This allows up to 848 concurrently outstanding entries to
  the sdfsdf function before one returns.  The default maxactive
  number is smaller, and can result in missed return probes.

- Support accessing of saved function arguments from within
  return probes.  These values are saved by a synthesized
  function-entry probe.

- Add substantial version/architecture checking in compiled probes to
  assert correct installation of debugging information and correct
  execution on a compatible kernel.

- Add probe-time checking for sufficient free stack space when probe
  handlers are invoked, as a safety improvement.

- Add an optional numeric parameter for begin/end probe specifications,
  to order their execution.  
     probe begin(10) { } /* comes after */ probe begin(-10) {}

- Add an optional array size declaration, which is handy for very small
  or very large ones.
     global little[5], big[20000] 

- Include some example scripts along with the documentation.

- Change the start-time allocation of probe memory to avoid causing OOM
  situations, and to abort cleanly if free kernel memory is short.

- Automatically use the kernel DWARF unwinder, if present, for stack
  tracebacks.

- Many minor bug fixes, performance, tapset, and error message
  improvements.