commit 13c822e0429ee71ff0fd2a7587afa582a1bae31c
author Rafael Cintron <rafael.cintron@microsoft.com> Thu Jul 17 15:22:36 2025 -0700
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> Thu Jul 17 15:22:36 2025 -0700
tree 629860e4f01e7273d8c10a4ab9811f532a6d8c65
parent f8d9d1c2155845e51312ca08acb6219293363460

Remove DXC fallbacks to WinSDK

Partial reland of "Improve DX compiler library loading": commit
a45d5b2b40d12d0f650e3f8cdd70a20c853ff5a0.

This CL removes DXC fallbacks to the WinSDK. To ensure compat with the
DXC version Dawn supports, building with DAWN_USE_BUILT_DXC=false
compiles out DXC loading code.

Adjusting load paths to be absolute will arrive in a followup change.

Original change's description:
> Reland "Reland "Improve DX compiler library loading""
>
> This is a reland of commit e579b628e5d5276086b6a2eaefa1718586bc7e18
>
> Add dawn_force_system_component_load for projects (like Skia) which
> require that Dawn load all compiler DLL from System32. Best security
> is to leave the default value which (now) loads compiler DLLs from the
> same directory as Dawn code.
>
> On Chromium builds (such as x86) which do not build DXC, place the
> DLLs from the SDK into the build folder to appease infra tools that
> copy the DLLs unconditionally.
>
> Improve DAWN_USE_BUILT_DXC to use the #define to skip loading the DLLs
> altogether.
>
> Original change's description:
> > Reland "Improve DX compiler library loading"
> >
> > This is a reland of commit e4d4669d79501b1acdd2bf017ba491b611d741da
> >
> > Remove build_with_chromium statements in test GN files that copy
> > DLLs. Rely on copies instructions which already exist with the D3D12
> > files.
> >
> > To appease Skia builds which do not depend on the Windows SDK,
> > fallback to system FXC if the local directory version is not found.
> >
> > Original change's description:
> > > Improve DX compiler library loading
> > >
> > > Previously, DX compiler DLLs were loaded using LoadLibrary with no path.
> > > D3D12 compiler DLLs were further sourced from the local user's SDK
> > > directory as a fallback.
> > >
> > > For better security, load DX compiler DLLs using full paths, with
> > > SEARCH_DLL_LOAD_DIR | SEARCH_DEFAULT_DIRS for better security. Scenarios
> > > such as Skia and x86 builds where we need dawn_use_built_dxc will
> > > fallback to FXC. No fallbacks to local user SDK directories.
> > >
> > > Bug:356665092
> > > Change-Id: Ib4148f9b89da694e3868b4f3c3c329a4b06ce922
> > > Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/229754
> > > Reviewed-by: Corentin Wallez <cwallez@chromium.org>
> > > Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>
> > > Reviewed-by: Antonio Maiorano <amaiorano@google.com>
> >
> > Bug: 356665092
> > Change-Id: Ic05d20c47c5db3021f9e38b724bf527bfba52a5e
> > Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/233216
> > Reviewed-by: Corentin Wallez <cwallez@chromium.org>
> > Reviewed-by: Antonio Maiorano <amaiorano@google.com>
> > Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>
>
> Bug: 356665092
> Change-Id: I83db06312db28123f9d5aee29617a8746768bb3d
> Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/234919
> Reviewed-by: Antonio Maiorano <amaiorano@google.com>
> Reviewed-by: Corentin Wallez <cwallez@chromium.org>
> Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>

Bug: 356665092
Change-Id: I83f14536ca9a484fd213750fa268cca2cd7b893a
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/252918
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Loko Kung <lokokung@google.com>
Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>