[PATCH] ci: use Visual Studio for win+meson job on GitHub Workflows

In 7304bd2bc39 (ci: wire up Visual Studio build with Meson, 2025-01-22) we have wired up a new CI job that builds and tests Git with Meson on a Windows machine. The expectation here was that this build uses the Visual Studio toolchain to do so, and that is true on GitLab CI. But on GitHub Workflows it is not the case because we've got GCC in our PATH, and thus Meson favors that compiler toolchain over Visual Studio's.

Fix this by explicitly asking Meson to use the Visual Studio toolchain. While this is only really required for GitHub Workflows, let's also pass the flag in GitLab CI so that we don't implicitly assume the toolchain that Meson is going to pick.

Reported-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
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Hi,

this patch addresses the issue reported by Johannes [1] where GitHub Workflows doesn't use the Visual Studio toolchain in the win+Meson job even though it should.

Builds for GitLab are at [2], GitHub at [3]. GitHub now uses the MSVC toolchain as expected [4].

Thanks!

Patrick

[1]: <3e9ccffc7474698947bdcb6d49b5d0728deadd08.1741256780.git.gitgitgadget@gmail.com>
[2]: https://gitlab.com/gitlab-org/git/-/merge_requests/318
[3]: https://github.com/git/git/pull/1909
[4]: https://github.com/git/git/actions/runs/13697111615/job/38302001801?pr=1909#step:5:16
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 .github/workflows/main.yml | 2 +-
 .gitlab-ci.yml             | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)