windows: gyp 0.5.0 made build time multiple times slower

[bzoz]

• Version: master
• Platform: Windows
• Subsystem: build files

What steps will reproduce the bug?

GYP update in #32698 made the build time rise from 3minutes to 16minutes at least on the latest MSBuild 16.7.0+b89cb5fde.

Additional information

Looks like the GYP change changed the genrated .vcxproj files a bit, e.g. embedtest.vcxproj:

diff "fast\embedtest.vcxproj" "slow\embedtest.vcxproj"
137,139c137,145
<     <ClCompile Include="src\node_snapshot_stub.cc"/>
<     <ClCompile Include="src\node_code_cache_stub.cc"/>
<     <ClCompile Include="test\embedding\embedtest.cc"/>
---
>     <ClCompile Include="src\node_snapshot_stub.cc">
>       <ObjectFileName>$(IntDir)\src\node_snapshot_stub.obj</ObjectFileName>
>     </ClCompile>
>     <ClCompile Include="src\node_code_cache_stub.cc">
>       <ObjectFileName>$(IntDir)\src\node_code_cache_stub.obj</ObjectFileName>
>     </ClCompile>
>     <ClCompile Include="test\embedding\embedtest.cc">
>       <ObjectFileName>$(IntDir)\test\embedding\embedtest.obj</ObjectFileName>
>     </ClCompile>
142a149
>       <ObjectFileName>$(IntDir)\tools\msvs\pch\node_pch.obj</ObjectFileName>

Looks like the <ObjectFileName> tags make the build not run in parallel, thus dramatically increasing the build time.

/cc @nodejs/build-files @nodejs/platform-windows

[targos]

I think this discussion is exactly about the issue: https://developercommunity.visualstudio.com/idea/586584/vs2017-cc-multi-processor-compilation-does-not-wor.html

It seems that we can improve it by only providing the directory name ending with a slash instead of the full file path: https://developercommunity.visualstudio.com/comments/586371/view.html
Another option is to try an experimental feature: https://developercommunity.visualstudio.com/comments/742133/view.html

I do not have the time to investigate these options.

Note that adding <ObjectFileName> was necessary to compile V8 because it has some files with duplicate names.

[bzoz]

@targos the experimental fix works, I'll make a PR

[bzoz]

PR in #35932