Remove '$dao->free()' part 1

[aydun]

See https://lab.civicrm.org/dev/core/issues/562

First round: remove lines exactly matching '$dao->free();'

[civibot]

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[seamuslee001]

@aydun can you rebase against current master please

[seamuslee001]

Jenkins retest this please

[aydun]

@eileenmcnaughton @seamuslee001 This was a quick test - a bit of perl hackery adapted from previous mass changes to docs - to remove exact matches of '$dao->free();' under the CRM tree, and then see how the test suite reacted. The tests ran cleanly here although I wonder how much the tests would actually pick up any issues related to this.

How do you want to segment and test this? There are matches under other directories and places where the variable is not '$dao' All can be picked up by tweaking the perl regexp.

Maybe:

• remove all '$dao->free()'
• as above but variants of 'dao'
• examine other lines calling '->free()' - but excluding calls to CRM_Core_Config::free()

Each stage requires progressively more review.

[eileenmcnaughton]

@aydun I'm pretty confident about ripping these out - but I'd probably merge 3-4 files worth now & a few after the rc with an increasing pace - starting with higher traffic files like CRM/Core/DAO.php perhaps in the first round since it would be there is we did see something.

[aydun]

@eileenmcnaughton Ok, here's 4 for starters

[seamuslee001]

Merging as per the tag