Odoo 12ce - Ubuntu

When clicking​ on Inventory -> Reporting -> Inventory Valuation, I get the AssertionError below.

I updated the code with the latest from the git repository.  I couldn't recreate on runbot, but the Traceback doesn't seem to touch any custom modules.

Another weird note is that twice (out of 40-50 attempts), it worked.  No idea why or what the difference was.

Any ideas?

Error:
Odoo Server Error

Traceback (most recent call last):
  File "/opt/odoo12/odoo/odoo/http.py", line 656, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)
  File "/opt/odoo12/odoo/odoo/http.py", line 314, in _handle_exception
    raise pycompat.reraise(type(exception), exception, sys.exc_info()[2])
  File "/opt/odoo12/odoo/odoo/tools/pycompat.py", line 87, in reraise
    raise value
  File "/opt/odoo12/odoo/odoo/http.py", line 698, in dispatch
    result = self._call_function(**self.params)
  File "/opt/odoo12/odoo/odoo/http.py", line 346, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "/opt/odoo12/odoo/odoo/service/model.py", line 97, in wrapper
    return f(dbname, *args, **kwargs)
  File "/opt/odoo12/odoo/odoo/http.py", line 339, in checked_call
    result = self.endpoint(*a, **kw)
  File "/opt/odoo12/odoo/odoo/http.py", line 941, in __call__
    return self.method(*args, **kw)
  File "/opt/odoo12/odoo/odoo/http.py", line 519, in response_wrap
    response = f(*args, **kw)
  File "/opt/odoo12/odoo/addons/web/controllers/main.py", line 966, in call_button
    action = self._call_kw(model, method, args, {})
  File "/opt/odoo12/odoo/addons/web/controllers/main.py", line 954, in _call_kw
    return call_kw(request.env[model], method, args, kwargs)
  File "/opt/odoo12/odoo/odoo/api.py", line 749, in call_kw
    return _call_kw_multi(method, model, args, kwargs)
  File "/opt/odoo12/odoo/odoo/api.py", line 736, in _call_kw_multi
    result = method(recs, *args, **kwargs)
  File "/opt/odoo12/odoo/addons/stock_account/wizard/stock_quantity_history.py", line 13, in open_table
    self.env['stock.move']._run_fifo_vacuum()
  File "/opt/odoo12/odoo/addons/stock_account/models/stock.py", line 527, in _run_fifo_vacuum
    fifo_valued_products |= self.env['product.product'].search([('categ_id', 'child_of', fifo_valued_categories.ids)])
  File "/opt/odoo12/odoo/odoo/models.py", line 1561, in search
    res = self._search(args, offset=offset, limit=limit, order=order, count=count)
  File "/opt/odoo12/odoo/addons/product/models/product.py", line 419, in _search
    return super(ProductProduct, self)._search(args, offset=offset, limit=limit, order=order, count=count, access_rights_uid=access_rights_uid)
  File "/opt/odoo12/odoo/odoo/models.py", line 4110, in _search
    query = self._where_calc(args)
  File "/opt/odoo12/odoo/odoo/models.py", line 3904, in _where_calc
    where_clause, where_params = e.to_sql()
  File "/opt/odoo12/odoo/odoo/osv/expression.py", line 1300, in to_sql
    assert len(stack) == 1
AssertionError