This patch does two things. First, it silences a number of compile-time
warnings in the msvc tools files, mainly those due to the fact that in
some cases we have more than one package per file. Second it supplies a
dummy Perl library with just enough of the Windows API referred to in
our code to let it run these checks cleanly, even on Unix machines where
the code is never supposed to run. The dummy library should only be used
for that purpose, as its README notes.
Adjust the way we detect the locale. As a result the minumum Windows
version supported by VS2015 and later is Windows Vista. Add some tweaks
to remove new compiler warnings. Remove documentation references to the
now obsolete msysGit.
Michael Paquier, somewhat edited by me, reviewed by Christian Ullrich.
Backpatch to 9.5
Code like
open(P, "cl /? 2>&1 |") || die "cl command not found";
does not actually catch any errors, because the exit status of the
command before the pipe is ignored. The fix is to look at $?.
This also gave the opportunity to clean up the logic of this code a bit.
