Adds the rcheevos library from RetroAchievements to the Dolphin Externals as a submodule. Change was verified to import correctly and build both via Visual Studio and via cmake ninja.
Doing so is not allowed (presumably because compilers are allowed to use a different algorithm for allocating between the two/store extra data such as the length of the array before the pointer).
This bug existed in the original implementation at https://web.archive.org/web/20140708092159/http://www.hydrogenaud.io/forums/index.php?showtopic=52235 and causes Valgrind to emit a warning. Note that this ended up happening even if DSPLLE and the DPL decoder are not enabled in Dolphin.
This cmake file directly sets CMAKE_<LANG>_FLAGS, which doesn't
show up in the COMPILE_COMMANDS target property and so our
dolphin_disable_warnings_msvc macro failes to remove it.
So we will just commit it out.
For some reason, when this is included, the linking step creates a temporary file in %TEMP% with a random name; the file is deleted afterwards and a new random name is used on a later build. Because this file doesn't exist on a later build, curl gets re-linked each time, and then all of the projects that depend on curl also get re-linked. This adds around 10 seconds to the build time even for small changes.
To make things worse, I don't think libcurl.rc does anything useful since we statically link curl; I believe the metadata contained in it only applies when building a dll. (It does seem to be included in curl.lib, but gets discarded when linking Dolphin.exe.)
See Build\x64\Release\curl\curl.tlog\Lib-link-cvtres.write.1.tlog for the log that shows this path (the file is also mentioned after setting Tools -> Options... -> Projects and Solutions -> Build and Run -> MSBuild project build output verbosity to diagnostic, but not in a useful way).
Use: callstack(0x80000000).
!callstack(value) works as a 'does not contain'.
Add strings to expr.h conditionals.
Use quotations: callstack("anim") to check symbols/name.
This is necessary to retain precision above 32 bits, but more importantly to prevent an expression like (0x80000000 | 1) from flipping the sign of the result.
We use Dolphin code (specifically Common's ASSERT) from ImGui, and that will use C++20 features in the next commit, so ImGui needs to be built with C++20 for that to work properly.
* moves dolphin-specific settings out of Base.props
* creates exports.props for externals, allowing to easily import
individual Externals
* corrects some cruft that accumulated and probably contributed
to msbuild overbuilding
