[issue30687] build.bat should locate msbuild.exe rather than vcvarsall.bat

[Steve Dower]

New submission from Steve Dower:

Due to how installation of Visual Studio 2017 has changed, it's very possible to end up with a valid install of the build tools without vcvarsall.bat being valid.

We only require MSBuild.exe to build, so we should find that tool and invoke it, rather than trying to configure the entire environment.

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assignee: steve.dower
components: Build, Windows
messages: 296218
nosy: paul.moore, steve.dower, tim.golden, zach.ware
priority: normal
severity: normal
stage: patch review
status: open
title: build.bat should locate msbuild.exe rather than vcvarsall.bat
type: compile error
versions: Python 3.5, Python 3.6, Python 3.7

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue30687>
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