Crash trying to load .jpg image via QImage

With a 32-bit build of Qt 5.12.1 or 5.12.2 or 5.12.3 (specifically "qt/5.12.1@bincrafters/stable" and "qt/5.12.2@bincrafters/stable" and "qt/5.12.3@bincrafters/stable" from conan (https://bintray.com/bincrafters/public-conan/qt%3Abincrafters)), the following usage of QImage will cause a crash in qjpeghandler.cpp: 

QImage i(R"(C:\test\Untitled.jpg)");

The following will not crash, however, it will also not load the image properly:

QImage i(R"("C:\test\Untitled.jpg")");
auto test = i.isNull(); // returns true...

This behavior can not be seen with 5.11 or a 64-bit build of 5.12.1/5.12.2.

Call stack:

I can't attach the .jpg, since Jira is giving me the following error (on any attachment, not just the jpg...):

My test file was simply an empty 600x600 .jpg created with Paint.