Git for Windows needs to ship with a lot of Unix tools that Git takes
for granted, such as `sed`, `awk`, a C compiler and a Unix shell, just
to name a few. In Git for Windows, these are provided by the MSYS2
project.
Part of these tools (such as `bash.exe`) use a POSIX emulation layer
("MSYS2 runtime", a friendly fork of the Cygwin runtime), but others
target a native Win32 toolchain, e.g. `git.exe`. There are multiple
flavors of that toolchain, and historically Git for Windows used MINGW64
on x64 Windows. This toolchain uses the old MSVC runtime, and therefore
the MSYS2 project deprecated it.
As a consequence, Git for Windows switches to UCRT64 with v2.56.0. That
flavor still uses GCC to compile native Win32 binaries, but targets the
Universal C Runtime ("UCRT"). Internally, this means that the new
`git.exe` is installed into a new prefix, `/ucrt64/`, whereas the old
`git.exe` was installed into `/mingw64/`.
A recently-upstreamed commit hard-codes this expectation even into the
CMake-based build, so that the built `git.exe` "knows where it lives"
and can ensure that the tools it expects on the `PATH` are found.
Naturally, this hard-coded MINGW64 needs to change to UCRT64 now, too.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
1cd6b7de52