[CMake][Win] Forwarding headers of WTF and PAL are copied twice in Visual Studio builds

[Fujii Hironori]

[CMake][Win] Forwarding headers of WTF and PAL are copied twice in Visual Studio builds

Here is the full build log: https://gist.github.com/fujii/84acffa6bd648c8af5bbac5b01ed954f
For example, DerivedSources/ForwardingHeaders/pal/system/Clock.h was copied twice in PALForwardingHeaders and PAL projects.

> 7>------ Build started: Project: PALForwardingHeaders, Configuration: Release x64 ------
> 7>Generating ../../../../DerivedSources/ForwardingHeaders/pal/system/Clock.h
> 23>------ Build started: Project: PAL, Configuration: Release x64 ------
> 23>Generating ../../../../DerivedSources/ForwardingHeaders/pal/system/Clock.h

[Fujii Hironori]

Created attachment 334797 [details]
Screenshot of Solution Explore

Those header files reside in both projects.

[Fujii Hironori]

I think we have two choices of solutions:

* Use cmake -E copy_if_different
* Copy in PAL target and Remove PALForwardingHeaders target

[Fujii Hironori]

One more way:

* Do not add those headers in WTF and PAL

[Fujii Hironori]

Created attachment 334798 [details]
WIP patch for solution #3

[Fujii Hironori]

Created attachment 334799 [details]
another WIP patch

(In reply to Fujii Hironori from comment #2)
> * Copy in PAL target and Remove PALForwardingHeaders target

It turns out this approach doesn't work as expected.
Because LLIntOffsetsExtractor needs forwarding header of JSC.
So JavaScriptCore and JavaScriptCoreForwardingHeaders targets should be separate.

I created another WIP patch of meta CMake approach.

[Don Olmstead]

(In reply to Fujii Hironori from comment #5)
> Created attachment 334799 [details]
> another WIP patch
> 
> (In reply to Fujii Hironori from comment #2)
> > * Copy in PAL target and Remove PALForwardingHeaders target
> 
> It turns out this approach doesn't work as expected.
> Because LLIntOffsetsExtractor needs forwarding header of JSC.
> So JavaScriptCore and JavaScriptCoreForwardingHeaders targets should be
> separate.
> 
> I created another WIP patch of meta CMake approach.

I'm trying to split the headers project into 2 in https://bugs.webkit.org/show_bug.cgi?id=183251 which would solve this issue.

WIP solution #3 is the route I would go after this but I would keep with the naming ${framework}_PUBLIC_FRAMEWORK_HEADERS

[Don Olmstead]

Created attachment 335009 [details]
Patch

Patch renaming WTF_HEADERS to WTF_PUBLIC_FRAMEWORK_HEADERS and PAL_HEADERS to PAL_PUBLIC_FRAMEWORK_HEADERS.

This stops the twice copying

[Konstantin Tokarev]

Comment on attachment 335009 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=335009&action=review

> Source/WTF/wtf/CMakeLists.txt:1
> +set(WTF_PUBLIC_FRAMEWORK_HEADERS

WTF_PUBLIC_HEADERS would be better IMO

[Don Olmstead]

Created attachment 335024 [details]
Patch

Updating based on review comments.

[Konstantin Tokarev]

Where WTF_PUBLIC_HEADERS is used?

[WebKit Commit Bot]

Comment on attachment 335024 [details]
Patch

Clearing flags on attachment: 335024

Committed r229572: <https://trac.webkit.org/changeset/229572>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Radar WebKit Bug Importer]

<rdar://problem/38402775>