commit https://github.com/vim/vim/commit/4b6a6dcbe7bd13170c4884cc17acb1eac2c633d1 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Feb 4 22:49:49 2016 +0100 patch 7.4.1261 Problem: Pending channel messages are garbage collected. Leaking memory in ch_sendexpr(). Leaking memory for a decoded JSON string. Solution: Mark the message list as used. Free the encoded JSON. Don't save the JSON string.

Tests for quickfix window's title     vim: set ft=vim :

STARTTEST
:so small.vim
:if !has('quickfix') | e! test.ok | wq! test.out | endif
:set efm=%E%f:%l:%c:%m
:cgetexpr ['file:1:1:message']
:let qflist=getqflist()
:call setqflist(qflist, 'r')
:copen
:let g:quickfix_title=w:quickfix_title
:wincmd p
:$put =g:quickfix_title
:/^Results/,$w test.out
:qa!
ENDTEST

Results of test_qf_title: