Please update the PR title to something more explanatory, as they are now included in merge commits.

Better now?

utACK 40c8a65

@theuni Can you take a look at the build system changes here please?

I wasn't comfortable reviewing e90d91c accurately, so I scripted it. Could you please update the commit message to make it a scripted diff? See here for an explanation: https://github.com/bitcoin/bitcoin/blob/master/doc/developer-notes.md#scripted-diffs

The script I used, which matches your commit, is:

sed -iE -e 's/"x\(yes\|no\|auto\)\?"/x\1/g' -e 's/test \(x\$[^ ]*\)/test "\1"/g' build-aux/m4/bitcoin_qt.m4

Did you use some tool or script for the m4 macros? I think it's fine, but I'm nervous about some issue turning up months from now because of an errant bracket.

No time for creating a script, sorry. I suggest that you do a comparison with

git diff --word-diff-regex=. --word-diff=color e90d91c^ e90d91c

for review; this shows the changes of this commit in the most compact form.

Just a final note regarding bitcoin's M4 stuff for configuring Qt: I now believe that this is the wrong way. Without the help of qmake it will always remain a guesswork what compiler flags should be really used, and what code should be used for static linking. Have a look at

http://repo.or.cz/ttfautohint.git/blob_plain/HEAD:/m4/autotroll.m4
http://repo.or.cz/ttfautohint.git/blob/HEAD:/configure.ac#l52
http://repo.or.cz/ttfautohint.git/blob/HEAD:/frontend/static-plugins.cpp.in

for my current solution. For example, if I configure ttfautohint for cross-building with mxe, static-plugins.cpp automatically contains the following code.

// This file is autogenerated by qmake. It imports static plugin classes for
// static plugins specified using QTPLUGIN and QT_PLUGIN_CLASS.<plugin> variables.
#include <QtPlugin>
Q_IMPORT_PLUGIN(QWindowsIntegrationPlugin)

FYI: autotroll has been updated with my changes and is now available from https://github.com/tsuna/autotroll.

@lemzwerg I'd really rather not change all this around arbitrarily. And I'd certainly not require qmake. Especially considering that they'll be replacing it with qbs in the future.

Everything but the last commit looks good to me (after addressing #11222 (comment)). I assume the last is probably ok too, but I'd rather not risk introducing some obscure new error if this doesn't fix a reported bug.

Needs update for @cfields' comments.

Closing in favour of #11711.