qt6-qtwebengine@6.9.2 build fails: alleged missing Metal Toolchain

[murrayE]

Under macOS Tahow 26.0 on ARM64, I'm trying to redo failed installation of qt6 sub-ports mcalhounfrom the sudo port migrate (migration from Sequoia). From main.log:

:info:build /opt/local/Library/Frameworks/Python.framework/Versions/3.13/bin/python3.13 ../../../../../qtwebengine-everywhere-src-6.9.2/src/3rdparty/chromium/third_party/angle/src/libANGLE/renderer/metal/shaders/metal_wrapper.py xcrun metal -c ../../../../../qtwebengine-everywhere-src-6.9.2/src/3rdparty/chromium/third_party/angle/src/libANGLE/renderer/metal/shaders/mtl_internal_shaders_autogen.metal -o gen/angle/mtl_internal_shaders_autogen.air --std=macos-metal2.1 -mmacosx-version-min=10.14
:info:build error: error: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain

However, I did install Metaltoolchain using xcodebuild, and Xcode > Settings > Components does show Metal Toolchain 26.0 (17A324) as installed.

[murrayE]

main.log

[reneeotten (Renee Otten)]

Yes, I am aware of that, have the same issue on Intel, and not found a solution yet.

[dlamija (Muhammed Ramiza)]

with a MetalToolchain install it still givee an error looking for metallib file

:info:build FileNotFoundError: [Errno 2] No such file or directory: '/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/metallib'

unfortunately there are not metallib but metal installed

/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/metal

[reneeotten (Renee Otten)]

Replying to dlamija:

with a MetalToolchain install it still givee an error looking for metallib file

:info:build FileNotFoundError: [Errno 2] No such file or directory: '/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/metallib'

unfortunately there are not metallib but metal installed

/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/metal

That could be the case, but it's according the error message not what causes the build to fail.

21938 :info:build error: error: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain

can you please upload a full build log - it seems you make it further in the build then me/us?

[dlamija (Muhammed Ramiza)]

Replying to reneeotten:

can you please upload a full build log - it seems you make it further in the build then me/us?

Actually xcodebuild -downloadComponent MetalToolchain had been used. let me upload the main.log

[dlamija (Muhammed Ramiza)]

main.log that search for metallib

[reneeotten (Renee Otten)]

It doesn't look like you uploaded the correct log file, there is no mention of metallib in there nor a build of qt6-qtwebengine.

Please do sudo port clean --all qt6-qtwebengine ; sudo port -dv install qt6-qtwebengine and if that fails (it will...), then add the log file that is mentioned in the error message to this ticket.

[reneeotten (Renee Otten)]

I already the ​upstream patch that supposedly should fix the issue but that doesn't work for me...

It's strange... the error I see is:

:info:build /opt/local/Library/Frameworks/Python.framework/Versions/3.13/bin/python3.13 ../../../../../qtwebengine-everywhere-src-6.9.2/src/3rdparty/chromium/third_party/angle/src/libANGLE/renderer/metal/shaders/metal_wrapper.py xcrun metal -c ../../../../../qtwebengine-everywhere-src-6.9.2/src/3rdparty/chromium/third_party/angle/src/libANGLE/renderer/metal/shaders/mtl_internal_shaders_autogen.metal -o gen/angle/mtl_internal_shaders_autogen.air --std=macos-metal2.1 -mmacosx-version-min=10.14

:info:build error: error: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain

however, if I execute the command myself in a shell it does work correctly. To be continued...

[dlamija (Muhammed Ramiza)]

Replying to reneeotten:

It doesn't look like you uploaded the correct log file, there is no mention of metallib in there nor a build of qt6-qtwebengine.

Please do sudo port clean --all qt6-qtwebengine ; sudo port -dv install qt6-qtwebengine and if that fails (it will...), then add the log file that is mentioned in the error message to this ticket.

Sorry my mistake; due to inspection on terminal, but whne upload drag from finder which happen open several location.

Since i already do all the cleaning, now unable to reproduce the same error. Sorry again

[reneeotten (Renee Otten)]

In 4f002852c924dc73501a68cc1080b7018e1eff9b/macports-ports (master):

qt6-webengine: fix build for macOS Tahoe

See: #73037

[markmentovai (Mark Mentovai)]

Hi. I fixed this in angle last week. You need to patch in ​https://chromium-review.googlesource.com/c/6955000 (angle 2f564f1ca07b1d2668d8639d98ea5ad51cc9cd35).

[reneeotten (Renee Otten)]

Replying to markmentovai:

Hi. I fixed this in angle last week. You need to patch in ​https://chromium-review.googlesource.com/c/6955000 (angle 2f564f1ca07b1d2668d8639d98ea5ad51cc9cd35).

Thanks Mark! For some reason the patch I added does work correctly on ​Tahoe and arm64 but it doesn't work for me locally on Intel. I will take a look into that link you provided and give it a go. I appreciate your help!

[markmentovai (Mark Mentovai)]

It looks like ​https://github.com/macports/macports-ports/commit/4f002852c924dc73501a68cc1080b7018e1eff9b only addresses the invocation of metallib, but ​https://chromium-review.googlesource.com/c/6955000 shows that you’ve got to handle metal too. Perhaps that’s why?

[reneeotten (Renee Otten)]

Replying to markmentovai:

It looks like ​https://github.com/macports/macports-ports/commit/4f002852c924dc73501a68cc1080b7018e1eff9b only addresses the invocation of metallib, but ​https://chromium-review.googlesource.com/c/6955000 shows that you’ve got to handle metal too. Perhaps that’s why?

As far as I can tell, the instance for metal was patched to use xcrun already in the ​downloaded package, only the metallib presumably needed patching. The part I don't understand anyways is why with the metallib patch it worked on the buildbot for arm64 but not locally for me on Intel ; that doesn't make sense, unless there is some subtle difference between full XCode / CLT installation.

Anyway, let's not worry about this right now. I will adapt the patch you linked above so that it applies to the Qt6QtWebengine source package and try to build locally. I'll report back here whether or not that worked!

[markmentovai (Mark Mentovai)]

unless there is some subtle difference between full XCode / CLT installation.

I don't think you can use the Metal toolchain with CLT only. I think it takes a full Xcode, and then an installation of the Metal toolchain. Could that be relevant to your x86-64 build?

[reneeotten (Renee Otten)]

Replying to markmentovai:

unless there is some subtle difference between full XCode / CLT installation.

I don't think you can use the Metal toolchain with CLT only. I think it takes a full Xcode, and then an installation of the Metal toolchain. Could that be relevant to your x86-64 build?

No, it cannot as the Portfile sets use_xcode yes so it will only work with a full XCode installation. The strange thing is that the same symptom (i.e., it builds on the buildbot after installing the Metal toolchain, but not locally for people) also seems to happen for the openjdk21 port 73008. I don't think we fully understand why that is happening yet...

[reneeotten (Renee Otten)]

still fails for me locally with the new patch... I think the issue could be due to the presence of /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/metal, which seems strange to me (as I just mentioned in Trac 73008 as well. Do you have that file as well Mark?

[markmentovai (Mark Mentovai)]

Do you have that file as well Mark?

Yes, that file is a part of Xcode.app, even at Xcode ≥ 26.0. In these newest versions of Xcode, …/XcodeDefault.xctoolchain/usr/bin/metal is really only capable of showing this message:

error: error: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain

This …/XcodeDefault.xctoolchain/usr/bin/metal is actually bit-for-bit identical to the metal driver at …/Metal.xctoolchain/usr/bin/metal (assuming the same version—the Metal toolchain is 26.0 17A324, and hasn’t been rebuilt to correspond to Xcode 26.0.1 17A400). The difference is that the one in Xcode.app’s XcodeDefault.xctoolchain no longer (since Xcode ≥ 26.0) has by …/usr/metal nearby, where the one in the independently installable Metal.xctoolchain does.

I haven’t tried this build on x86_64 yet but I can. It might be more expedient if you share the error you’re seeing?

[reneeotten (Renee Otten)]

I fiddled around with things and messed up so the log is gone; I'll have to rebuild again. But the error is always the same: error: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain I will try to build again and upload the main.log here once finished.

I've also pushed the changes to ​my branch; if you don't mind to check whether the patch is correct. As I said, I needed to change it so that it would apply to the qtwebengine source archive. But I *think* I did so correctly.

[markmentovai (Mark Mentovai)]

Your branch looks right to me, Renee.

No idea why qt would have fixed this for metallib but not metal, but they’ll catch up when they sync to the latest Chromium (including angle) again.

There’s another option if the Metal toolchain is too much trouble now: in the Chromium/angle bug report for this last week (​https://crbug.com/445400016), I pointed out the possibility of using the metal_internal_shader_compilation_supported switch:

There’s also the possibility of throwing the ​metal_internal_shader_compilation_supported switch, which exists in part to support cross-compilation, where the Metal toolchain is not available. This was largely introduced in ​https://chromium-review.googlesource.com/c/4974918 (2023-10-25), but I presume we don’t want to forgo prebuilt shaders.

This option would prevent the angle build from using metal or metallib at all, at the expense of not prebuilding any Metal shaders. I didn’t want to give up on prebuilt shaders in Chromium, but it might not be so bad as a temporary measure here. Especially considering that MacPorts build environments are less controlled than Chromium/Chrome’s, and that there seem to be cross-user bugs around accessing the MetalToolchain cryptex, it might be the right compromise.

[reneeotten (Renee Otten)]

main.log after final patch

[markmentovai (Mark Mentovai)]

It seems like everything remaining here that’s relevant is being discussed in greater detail on ​bug 73008. In general, try ​comment 22: run xcodebuild -showComponent MetalToolchain as your MacPorts user. Additionally, for x86-64, try ​comment 28: if another user has mounted the MetalToolchain filesystem, have them unmount it: diskutil eject $(xcodebuild -showComponent MetalToolchain | sed -E -n -e 's/^Toolchain Search Path: (.*)$/\1/p').

[murrayE]

Latest qt6-qtweb3ngine @6.9.2_0 build OK on Tahoe arm64.

[dlamija (Muhammed Ramiza)]

qt60qtwebnwgine 6.9.2 instlled successfully with current patch. Unfortunately the package had been updated to 6.9.3 which produce the same problem again.

:info:build FAILED: [code=1] gen/angle/mtl_internal_shaders_autogen.air 
:info:build /opt/local/Library/Frameworks/Python.framework/Versions/3.13/bin/python3.13 ../../../../../qtwebengine-everywhere-src-6.9.3/src/3rdparty/chromium/third_party/angle/src/libANGLE/renderer/metal/shaders/metal_wrapper.py xcrun metal -c ../../../../../qtwebengine-everywhere-src-6.9.3/src/3rdparty/chromium/third_party/angle/src/libANGLE/renderer/metal/shaders/mtl_internal_shaders_autogen.metal -o gen/angle/mtl_internal_shaders_autogen.air --std=macos-metal2.1 -mmacosx-version-min=10.14
:info:build error: error: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain

[jhoyt4]

I'm experiencing the same issue. 6.9.2 finally installed, but 6.9.3 shows the error @dlamija reported.

[markemer (Mark Anderson)]

It's funny, I had an issue system wide with xcrun metal giving that error, but I managed to fix it, but I still get that error when building 6.9.3

Edit: Gonna give a proper clean a try as I see there is a patch file that should fix things.

Edit 2: So, the gn file does appear to be patched but it appears to fail at the same place in libANGLE, weird. Continuing to investigate.

[yesyves]

I have this error happening for the first time with 6.10.0 today

[markemer (Mark Anderson)]

Yeah, I can't seem to upgrade 6.9.2 to 6.9.3 or 6.10.0, despite being able to run xcrun metal at the command line for a while, and it being mounted via cryptexd.

[jhoyt4]

no joy with 6.10.0

[15/15806] ACTION //third_party/angle/src/libANGLE/renderer/metal:angle_metal_internal_shaders_to_air(//build/toolchain/mac:clang_arm64)
FAILED: [code=1] gen/angle/mtl_internal_shaders_autogen.air 
/opt/local/Library/Frameworks/Python.framework/Versions/3.13/bin/python3.13 ../../../../../qtwebengine-everywhere-src-6.10.0/src/3rdparty/chromium/third_party/angle/src/libANGLE/renderer/metal/shaders/metal_wrapper.py xcrun metal -c ../../../../../qtwebengine-everywhere-src-6.10.0/src/3rdparty/chromium/third_party/angle/src/libANGLE/renderer/metal/shaders/mtl_internal_shaders_autogen.metal -o gen/angle/mtl_internal_shaders_autogen.air --std=macos-metal2.1 -mmacosx-version-min=10.14
error: error: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain

[markmentovai (Mark Mentovai)]

See ​bug 73008 comment 54. I gave recovery steps there that will hopefully work for everyone.

[murrayE]

After applying the method from ​https://trac.macports.org/ticket/73008#comment:54, the buil still failed when I attempted to upgrade to qt6-qtwebengine @ 6.10.0_0 under macOS Tahoe 26.0.1 on an M4 Mac.

[markmentovai (Mark Mentovai)]

Replying to murrayE:

After applying the method from ​https://trac.macports.org/ticket/73008#comment:54, the buil still failed when I attempted to upgrade to qt6-qtwebengine @ 6.10.0_0 under macOS Tahoe 26.0.1 on an M4 Mac.

“Still failed” on its own isn’t much to go on.

I’ll show you how I did this. If you follow all of these commands in the right order and it still doesn’t work for you, can you share the output of what you see to help troubleshoot?

(Yeah, it’s a lot. But there are several things that can go wrong with this, particularly in a multi-user scenario, and going through everything methodically and showing all work really helps verify that all of the steps were followed to the letter, and helps pinpoint where any problems might exist if any part of the process needs to be refined.)

admin@axilla zsh% sw_vers
ProductName:		macOS
ProductVersion:		26.0.1
BuildVersion:		25A362

admin@axilla zsh% xcodebuild -version
Xcode 26.0.1
Build version 17A400

admin@axilla zsh% arch
arm64

admin@axilla zsh% system_profiler SPHardwareDataType | grep -E 'Model Identifier|Chip'
      Model Identifier: Mac16,5
      Chip: Apple M4 Max

admin@axilla zsh% xcodebuild -downloadComponent MetalToolchain
Beginning asset download...
Downloaded asset to: /System/Library/AssetsV2/com_apple_MobileAsset_MetalToolchain/4ab058bc1c53034b8c0a9baca6fba2d2b78bb965.asset/AssetData/Restore/022-17211-415.dmg
Done downloading: Metal Toolchain 17A324.

admin@axilla zsh% xcodebuild -showComponent MetalToolchain
Asset Path: /System/Library/AssetsV2/com_apple_MobileAsset_MetalToolchain/4ab058bc1c53034b8c0a9baca6fba2d2b78bb965.asset/AssetData
Build Version: 17A324
Status: installed
Toolchain Identifier: com.apple.dt.toolchain.Metal.32023
Toolchain Search Path: /private/var/run/com.apple.security.cryptexd/mnt/com.apple.MobileAsset.MetalToolchain-v17.1.324.0.t40qgS

admin@axilla zsh% sudo ls -l ~macports/Library/Developer/Xcode/XcodeToMetalToolchainIndexMapping.plist
-rw-r--r--  1 macports  macports  442 Oct 24 14:08 /opt/local/var/macports/home/Library/Developer/Xcode/XcodeToMetalToolchainIndexMapping.plist

admin@axilla zsh% sudo --user=macports xcodebuild -showComponent MetalToolchain
Asset Path: /System/Library/AssetsV2/com_apple_MobileAsset_MetalToolchain/4ab058bc1c53034b8c0a9baca6fba2d2b78bb965.asset/AssetData
Build Version: 17A324
Status: installed
Toolchain Identifier: com.apple.dt.toolchain.Metal.32023
Toolchain Search Path: /private/var/run/com.apple.security.cryptexd/mnt/com.apple.MobileAsset.MetalToolchain-v17.1.324.0.t40qgS

admin@axilla zsh% sudo ls -l ~macports/Library/Developer/Xcode/XcodeToMetalToolchainIndexMapping.plist
-rw-r--r--  1 macports  macports  442 Oct 24 14:14 /opt/local/var/macports/home/Library/Developer/Xcode/XcodeToMetalToolchainIndexMapping.plist

admin@axilla zsh% sudo --user=macports xcodebuild -find metal
/var/run/com.apple.security.cryptexd/mnt/com.apple.MobileAsset.MetalToolchain-v17.1.324.0.t40qgS/Metal.xctoolchain/usr/bin/metal

admin@axilla zsh% sudo --user=macports xcrun --find metal
/var/run/com.apple.security.cryptexd/mnt/com.apple.MobileAsset.MetalToolchain-v17.1.324.0.t40qgS/Metal.xctoolchain/usr/bin/metal

admin@axilla zsh% sudo rm -f "$(sudo --user=macports getconf DARWIN_USER_TEMP_DIR)/xcrun_db"

admin@axilla zsh% sudo --user=macports xcrun --find metal
/var/run/com.apple.security.cryptexd/mnt/com.apple.MobileAsset.MetalToolchain-v17.1.324.0.t40qgS/Metal.xctoolchain/usr/bin/metal

admin@axilla zsh% sudo --user=macports xcrun metal --version
Apple metal version 32023.830 (metalfe-32023.830.2)
Target: air64-apple-darwin25.0.0
Thread model: posix
InstalledDir: /private/var/run/com.apple.security.cryptexd/mnt/com.apple.MobileAsset.MetalToolchain-v17.1.324.0.t40qgS/Metal.xctoolchain/usr/metal/current/bin

admin@axilla zsh% sudo --preserve-groups port install qt6-qtwebengine
--->  Fetching distfiles for qt6-qtwebengine
--->  Attempting to fetch qtwebengine-everywhere-src-6.10.0.tar.xz from https://distfiles.macports.org/qt6
--->  Verifying checksums for qt6-qtwebengine
--->  Extracting qt6-qtwebengine
--->  Applying patches to qt6-qtwebengine
--->  Configuring qt6-qtwebengine
--->  Building qt6-qtwebengine
--->  Staging qt6-qtwebengine into destroot
--->  Installing qt6-qtwebengine @6.10.0_0
--->  Activating qt6-qtwebengine @6.10.0_0
--->  Cleaning qt6-qtwebengine
--->  Updating database of binaries
--->  Scanning binaries for linking errors
--->  No broken files found.
--->  No broken ports found.

[murrayE]

The build succeeded now when I followed also the steps in the displayed code following "Done" at ​https://trac.macports.org/ticket/73008#comment:54

[jhoyt4]

@markmentovai - That got me back up and running. Thank you.

[reneeotten (Renee Otten)]

thanks Mark - this indeed worked! I will update the Wiki page with your instructions.

[reneeotten (Renee Otten)]

see TahoeProblems for a workaround. Likely upcoming MacPorts and XCode versions will resolve this completely.

[markmentovai (Mark Mentovai)]

#73180 seeks a build of this port on the buildbot now that #73160 is fixed and MacPorts 2.11.6 has been released.