[PATCH v5 0/8] gdb: split array and string limiting options

[Maciej W. Rozycki]

Hi,

 Sadly I have received no feedback for v4 of the series other than the 
docs (thank you, Eli!), so here is v5 with the documentation parts updated 
only for Andrew's original proposal to split the `set/show print elements' 
options into two, so that there are separate `set/show print characters' 
options to control how many characters of a string are printed.

 Following earlier discussion for compatibility with existing setups I 
have implemented a mechanism to make the `set print characters' setting 
follow that of `set print elements' by default.  Consequently what was a 
single change has now grown into a patch series.

 In this series I fix some preexisting issues in the area first, implement 
the general framework for extra literals used with integer settings second 
and then add the original change for `set print characters' from Andrew, 
adjusted accordingly, followed by a testsuite update as a separate change. 
This is so as to ensure the semantics of the existing `set print elements' 
knob hasn't changed in the default `set print characters' state (a small 
update for the test suite is nevertheless included with the `set print 
characters' command proper, because inevitably the relevant commands that 
list commands now print additional entries, plus there's been a minimal 
test case update included for the verification of setting defaults).

 Since I have noticed some v4 hunks to apply with significant line number 
changes (meaning larger code rearrangements) and also Python 2 support to 
have been removed (my original builds used it) I have re-regression-tested 
the changes (with the build switched to Python 3), again with a native 
`x86_64-linux-gnu' configuration.  I have also visually examined the 
result of the updated changes to the GDB manual in the info and PDF 
formats.

 See individual change descriptions for details.

 OK to apply?

  Maciej