QFont intialized before QApplication causes segfault with static Qt

[oliverdaniell]

Initialization of fonts before QApplication is not valid and causes a segfault when linking statically against Qt. This is caused by the initialization of non-local variables before main. eg.

const auto BG_FONT = ::profiler_gui::EFont("Helvetica", 10, QFont::Bold);

This can be fixed by replacing the above with

auto const & BG_FONT() { static const auto BG_FONT = ::profiler_gui::EFont("Helvetica", 10, QFont::Bold); return BG_FONT; }

[oliverdaniell]

If you agree with the fix I can create a merge request

[yse]

@oliverdaniell thanks for report.
Of course, you can create request - it will be good!

[cas4ey]

local static QFont may cause problem on VS2013 because it has no c++11 magic statics support.
Please, move it into EASY_GLOBALS

[oliverdaniell]

The issue came up on gcc 5.4 so I don't think it's related to differences in the handling of static between c++98 and c++11 (I assume by c++11 magic statics you mean the thread safe initialization?).

I'm not sure why the code works when linking dynamically against Qt. From the doc

Note that a QGuiApplication instance must exist before a QFont can be used

Anyway EASY_GLOBALS looks like the logical place to put it so I will get that done tomorrow.

[cas4ey]

The issue came up on gcc 5.4 so I don't think it's related to differences in the handling of static between c++98 and c++11 (I assume by c++11 magic statics you mean the thread safe initialization?).

Yes, I mean thread safe initialization. I just wanted to say that hiding static QFont inside a function would add additional problems for VS2013 users (and gcc < 4.3) - there are a lot of them still.

Anyway EASY_GLOBALS looks like the logical place to put it so I will get that done tomorrow.

Nice 👍