https://bugs.winehq.org/show_bug.cgi?id=42282
--- Comment #10 from DX099 temptempor@gmail.com --- Thanks for the tips.
I've had to nitpick one more commit and downgrade my flex lib to <= 2.6.1 in addition of the the tips you got me.
Wine eventually compiled but now it can't run Steam. Clean profile, clean install in the new profile et all... Log file attached.