Richard Thomson LegalizeAdulthood

Porting from MFC to wxWidgets

This is a step-by-step guide for porting an application from MFC to wxWidgets based on my experience in porting Hippy.

Our case study is the open source fractal generator Iterated Dynamics, a fork of FRACTINT.
This is a 30 year old code base that started as a 16-bit MS-DOS program written in C and 16-bit x86 assembly.
The code base has contributions from many, many authors over the years.
Source formatting and identifier conventions are varied due to the large number of authors.
Source code organization has been tortured by the constraints of early MS-DOS programs operating in a limited amount of physical memory and the use of overlays.
Conditional compilation was sprinkled throughout to enable various debugging facilities or experiments in alternative implementations.
As C does not have inline functions, there are some places that heavily use preprocessor macros.
Some of the functions are [exceedingly long*](https://github.com/LegalizeAdulthood

Characteristics of an embedded environment
- Bare metal interaction with hardware
- No operating system
- No virtual memory
- No C/C++ runtime
No RTTI

Won't talk about preprocessor tricks
Topic is very deep! To drill further, consult one or more of these books:
- 2001: Modern C++ Design: Generic Programming and Design Patterns Applied by Andrei Alexandrescu
- 2004: C++ Template Metaprogramming: Concepts, Tools, and Techniques from Boost and Beyond by David Abrahams and Aleksey Gurtovoy
- 2017: C++ Templates: The Complete Guide (2nd Edition) by David Vandevoorde, Nicolai M. Josuttis, Douglas Gregor
Template Review
- Template expansion
Function Template

	# run this script with sudo
	# From <https://askubuntu.com/questions/355565/how-do-i-install-the-latest-version-of-cmake-from-the-command-line>
	apt remove --purge --auto-remove cmake
	apt update
	apt install -y software-properties-common lsb-release && \
	apt clean all
	wget -O - https://apt.kitware.com/keys/kitware-archive-latest.asc 2>/dev/null \| gpg --dearmor - \| tee /etc/apt/trusted.gpg.d/kitware.gpg >/dev/null
	apt-add-repository "deb https://apt.kitware.com/ubuntu/ $(lsb_release -cs) main"
	apt update
	apt install kitware-archive-keyring

	comp.lang.c++ #1074341 (1)
	From: Andrey Tarasevich <[email protected]>
	[1] A counterintuitive breaking change related to new comparisons
	Date: Mon Jan 03 10:48:42 MST 2022
	Lines: 42

	A colleague discovered that switching from `-stc=c++17` to `-std=c++20`
	in their project resulted in a different behavior from some associative
	containers. A bit of research allowed to narrow down the culprit to what
	can be demonstrated by the following minimalist example

	TEST( Foo, foo )
	{
	int failures = 0;
	for (int i = 0; i < 50; ++i) {
	EXPECT_TRUE( i % 2 == 0 ) << ([&failures]() { ++failures; return ""; })();
	}
	if (failures > 0) {
	std::cout << "There were " << failures << " failures.\n";
	}
	}