"Professional CMake" book suggest the following:
"Targets should build successfully with or without compiler support for precompiled headers. It
should be considered an optimization, not a requirement. In particular, do not explicitly include a
precompile header (e.g. stdafx.h) in the source code, let CMake force-include an automatically
generated precompile header on the compiler command line instead. This is more portable across
the major compilers and is likely to be easier to maintain. It will also avoid warnings being
generated from certain code checking tools like iwyu (include what you use)."
Therefore, removed the "#include <PreCompiled.h>" from sources, also
there is no need for the "#ifdef _PreComp_" anymore
only 4 of these warnings are still relevant, CMake shall be used to disable them
Compiler definitions:
NOMINMAX:
* is already globally defined in SetGlobalCompilerAndLinkerSettings.cmake
WIN32_LEAN_AND_MEAN:
* use CMake target_compile_options on relevant targets
Warnings that still occur:
C4251, C4273, C4275: all related to dllimport / export
* use CMake target_compile_options on relevant targets
C4661: no suitable definition provied for explicit template instantiation request
* triggered in Mesh because of Vector3D in Base - not all functions are defined in header
* use CMake target_compile_options on relevant targets
Warnings that are Currently not triggered (fix code if they appear again):
C4005: macro redefinition
C4244: argument conversion, possible loss of data
C4267: conversion from size_t to type, possible loss of data
C4305: truncation from type1 to type2
* only occurrence disabled in Reader.cpp
C4522: multiple assignment operator specified
C5208: unnamed class in typedef name
Obsolete Compiler warnings:
C4181: not mentioned in Microsoft docs anymore
C4290: C++ exception specification ignored except to indicate a function is not __declspec(nothrow)
* throw(optional_type_list) deprecated in C++17
C4482: nonstandard extension used: enum 'enumeration' used in qualified name
* not generated for compilers that support C++11
C4503: 'identifier': decorated name length exceeded, name was truncated
* obsolete since Visual Studio 2017
C4786: not mentioned in Microsoft docs anymore
Previously the code defined compatiblity usings in `QtOpenGL.h` header,
which I think was added for backwards compatiblity with previous Qt
OpenGL widgets.
As far as I can tell, this is not necessary anymore, and can be cleaned
up.
(found while searching for the build error on armhf/armel on Debian
buildds, once resolved will make an additional PR for that.)
$grep -r GL_MULTISAMPLE src/
yields:
src/Mod/Sandbox/Gui/Overlay.cpp: #ifndef GL_MULTISAMPLE
src/Mod/Sandbox/Gui/Overlay.cpp: #define GL_MULTISAMPLE 0x809D
src/Mod/Sandbox/Gui/GLGraphicsView.cpp:#ifndef GL_MULTISAMPLE
src/Mod/Sandbox/Gui/GLGraphicsView.cpp:#define GL_MULTISAMPLE 0x809D
-> The defines are defined, but never used in the compilation unit
