[vtk] Avoid stdext::checked_array_iterator.

[Oleg2]

Fixes #51766.

What this fixes

VTK's bundled (pre-7.0) copy of fmtlib at ThirdParty/diy2/vtkdiy2/include/vtkdiy2/fmt/format.h references stdext::checked_array_iterator under #ifdef _SECURE_SCL. This extension has been removed from the MSVC standard library in MSVC 14.51 (VS 2026 Preview), so the build fails with:

error C2653: 'stdext': is not a class or namespace name
error C2061: syntax error: identifier 'checked_array_iterator'

(full failure log in #51766)

Resolution

Drop the _SECURE_SCL branch and keep only the raw-pointer fallback. The patched make_checked / checked_ptr aliases become unconditional pass-throughs. This is the same approach already accepted in vcpkg for the same removal across five other ports:

PR	Port
#51750	cpprestsdk
#51774	breakpad
#51749	duckdb
#51753	ampl-mp
#51785	luminoengine

Files

• ports/vtk/diy2-fmt-remove-stdext-checked-array-iterator.patch — the source patch
• ports/vtk/portfile.cmake — register the patch
• ports/vtk/vcpkg.json — port-version 15 → 16
• versions/v-/vtk.json, versions/baseline.json — version DB bump (via vcpkg x-add-version vtk)

Local verification

Built vtk[core]:x64-windows against this overlay port using MSVC 14.51.36231 (VS 2026 Preview, generator Visual Studio 18 2026). The failing vtkDIYDataExchanger.cxx translation unit now compiles cleanly.

Manifest

• Changes comply with the maintainer guide.
• SHA512s are updated for each updated download. (no source changes)
• The "supports" clause reflects platforms that may be built. (unchanged)
• Any fixed CI baseline entries are removed from that file. (none applicable)
• Any patches that are no longer applied are deleted from the port's directory. (none)
• The version database is fixed by rerunning ./vcpkg x-add-version --all and committing the result.
• Only one version is added to each modified port's versions file.

[Oleg2]

Withdrawing — switching to a local-only patch in my private vcpkg checkout. The patch (ports/vtk/diy2-fmt-remove-stdext-checked-array-iterator.patch) and its construction notes remain available in the commit if anyone wants to revive it as their own PR.

[BillyONeal]

Is there something wrong with it? (Why withdraw it? Would rather give you credit for the fix if it actually fixes)

To be clear I have not reviewed, I just saw linked to my other PR

[drescherjm]

This patch seems to have worked for me in my local port. Although I am on an older version of the vtk port than the current.

vtk[cgns,core,libharu,libtheora,netcdf,proj,seacas,sql]:x64-windows@9.3.0-pv5.12.1#15 package ABI: accdcd3c7beea8fc4108a4ccd3eb68d053af928ae7a0258325e5aede226ddc79 Building vtk[cgns,core,libharu,libtheora,netcdf,proj,seacas,sql]:x64-windows@9.3.0-pv5.12.1#15... X:\vcpkgbased\DICOMUtilities\vcpkg/ports\vtk: info: installing overlay port from here -- Using cached Kitware-VTK-09a76bc55b37caad94d0d8ebe865caaed1b438af.tar.gz -- Extracting source X:/vcpkgbased/vcpkg/downloads/Kitware-VTK-09a76bc55b37caad94d0d8ebe865caaed1b438af.tar.gz -- Applying patch ffmpeg.diff -- Applying patch ffmpeg-8.diff -- Applying patch FindLZMA.patch -- Applying patch FindLZ4.patch -- Applying patch libproj.patch -- Applying patch mysql.diff -- Applying patch pegtl.patch -- Applying patch pythonwrapper.patch -- Applying patch NoUndefDebug.patch -- Applying patch fix-using-hdf5.patch -- Applying patch FindExpat.patch -- Applying patch cgns.patch -- Applying patch vtkm.patch -- Applying patch afxdll.patch -- Applying patch vtkioss.patch -- Applying patch jsoncpp.patch -- Applying patch iotr.patch -- Applying patch fast-float.patch -- Applying patch fix-exprtk.patch -- Applying patch devendor_exodusII.patch -- Applying patch remove-prefix-changes.patch -- Applying patch hdf5helper.patch -- Applying patch opencascade-7.8.0.patch -- Applying patch no-libharu-for-ioexport.patch -- Applying patch no-libproj-for-netcdf.patch -- Applying patch octree.patch -- Applying patch fix-tbbsmptool.patch -- Applying patch backport-bda8324.diff -- Applying patch use-compile-tools.diff -- Applying patch zspace.diff -- Applying patch mpi-language.diff -- Applying patch fix-eigen3.patch -- Applying patch diy2-fmt-remove-stdext-checked-array-iterator.patch -- Using source at X:/vcpkgbased/vcpkg/buildtrees/vtk/src/aed1b438af-00b856e7db.clean

-- Configuring x64-windows
-- Building x64-windows-dbg
-- Building x64-windows-rel
-- Installing: X:/vcpkgbased/vcpkg/packages/vtk_x64-windows/tools/vtk/vtkProbeOpenGLVersion-9.3.exe
-- Installing: X:/vcpkgbased/vcpkg/packages/vtk_x64-windows/tools/vtk/vtkTestOpenGLVersion-9.3.exe
-- Performing post-build validation


[drescherjm]

Oops, sorry for the noise. I didn't realize a different version of this patch was merged and was actually in the current port.