### Author:  [@Sidelobe](https://discourse.cmake.org/u/Sidelobe)
#### Post date: [July 10, 2024, 9:29am UTC](https://discourse.cmake.org/t/cmake-3-30-doesnt-let-me-use-archs-standard-to-set-cmake-osx-architectures/11209/1 "2024-07-10T09:29:07Z")
Cmake 3.30 seems to have broken my projects that build universal binaries (arm64;x86\_64)
I use this to create universal binaries when building via Xcode:
```cmake
if(CMAKE_GENERATOR STREQUAL "Xcode")
set(CMAKE_OSX_ARCHITECTURES $(ARCHS_STANDARD) CACHE STRING "")
endif()
```
Until Cmake 3.29.6 this still worked fine. I’m using Xcode 15.1.
Now it seems the `$(ARCHS_STANDARD)` (which is resolved by Xcode) can no longer be used because of some “consistency check” that probably happens before this variable is resolved.
This is the commit that causes a FATAL\_ERROR
>
>
> Not all compilers that can be used on APPLE platforms will respect
> the architect…ure(s) set in CMAKE\_OSX\_ARCHITECTURES and some will
> not raise an error if they are unable to do this. For instance,
> GCC will accept ignore additional architectures specified after the
> first -arch XXX (with a non-fatal warning) and will even link the
> simple test applications used in the ABI determination (and other
> tests that don't require external libraries) if an architecture
> is requested for which it doesn't have the required "multilib"
> set-up.
>
> Prevent unexpected build results or build failures that may occur
> after a lengthy build process: verify that the binary used to obtain
> the ABI information contains the requested architectures.
>
> Fixes: #25952
```auto
The C compiler targets architectures:
"x86_64;arm64"
but CMAKE_OSX_ARCHITECTURES is
"$(ARCHS_STANDARD)"
```
Is this a newly-introduced Cmake bug? Or is my way of using `$(ARCHS_STANDARD)` not proper or supported anymore?
If I set it explicitly to `set(CMAKE_OSX_ARCHITECTURES "x86_64;arm64" CACHE STRING "")`, everything works as expected.
---
### Author:  [@ClausKlein](https://discourse.cmake.org/u/ClausKlein)
#### Post date: [July 10, 2024, 9:52am UTC](https://discourse.cmake.org/t/cmake-3-30-doesnt-let-me-use-archs-standard-to-set-cmake-osx-architectures/11209/2 "2024-07-10T09:52:25Z")
do you want to use an environment value?
```cmake
if(CMAKE_GENERATOR STREQUAL "Xcode")
set(CMAKE_OSX_ARCHITECTURES $ENV{ARCHS_STANDARD} CACHE STRING "")
endif()
```
---
### Author:  [@Sidelobe](https://discourse.cmake.org/u/Sidelobe)
#### Post date: [July 10, 2024, 10:12am UTC](https://discourse.cmake.org/t/cmake-3-30-doesnt-let-me-use-archs-standard-to-set-cmake-osx-architectures/11209/3 "2024-07-10T10:12:20Z")
`ARCHS_STANDARD` is not defined as an environment variable (?)
Or did you mean manually defining an env variable ARCHS\_STANDARD and assigning it " `"x86_64;arm64"`?
I thought about running `xcodebuild -showBuildSettings | grep ARCHS_STANDARD` from within Cmake, but this requires an existing Xcode project.
---
### Author:  [@ClausKlein](https://discourse.cmake.org/u/ClausKlein)
#### Post date: [July 10, 2024, 4:33pm UTC](https://discourse.cmake.org/t/cmake-3-30-doesnt-let-me-use-archs-standard-to-set-cmake-osx-architectures/11209/4 "2024-07-10T16:33:11Z")
> [@Sidelobe](#):
>
> `ARCHS_STANDARD`
It seems to me that Xcode expect an environment var?
see [TN3117: Resolving architecture build errors on Apple silicon | Apple Developer Documentation](https://developer.apple.com/documentation/technotes/tn3117-resolving-build-errors-for-apple-silicon)
---
### Author:  [@Sidelobe](https://discourse.cmake.org/u/Sidelobe)
#### Post date: [July 10, 2024, 7:15pm UTC](https://discourse.cmake.org/t/cmake-3-30-doesnt-let-me-use-archs-standard-to-set-cmake-osx-architectures/11209/5 "2024-07-10T19:15:33Z")
I’m not following you…
`$(ARCHS_STANDARD)` is a variable _defined by Xcode_, not an enviroment variable.
with this `set(CMAKE_OSX_ARCHITECTURES $(ARCHS_STANDARD) CACHE STRING "")` I’m assigning the literal string `$(ARCHS_STANDARD)` to `CMAKE_OSX_ARCHITECTURES`. Xcode will later resolve `$(ARCHS_STANDARD)` to e.g. “arm64 x86\_64”
That is not the problem – CMakeCache.txt shows the correct entry:
`CMAKE_OSX_ARCHITECTURES:STRING=$(ARCHS_STANDARD)`
The problem is that, since Cmake 3.30, Cmake will abort because of some ‘consistency check’ because it cannot resolve $(ARCHS\_STANDARD) (which is obvious).
This is the ‘breaking change’: [APPLE: Check if compilers respect CMAKE\_OSX\_ARCHITECTURES · Kitware/CMake@db409e5 · GitHub](https://github.com/Kitware/CMake/commit/db409e5e681e75a322ee11c7bb0ad8d2be90cf5e)
If you are suggesting “pre-resolving” $(ARCHS\_STANDARD) e.g. with `xcodebuild -showBuildSettings | grep ARCHS_STANDARD` and saving it an environment variable and then using that within Cmake – yes, that would work, I guess.
But I don’t get why this should be necessary - the “literal string” method has worked with Cmake for years (decades).
---
### Author:  [@craig.scott](https://discourse.cmake.org/u/craig.scott)
#### Post date: [July 10, 2024, 10:21pm UTC](https://discourse.cmake.org/t/cmake-3-30-doesnt-let-me-use-archs-standard-to-set-cmake-osx-architectures/11209/6 "2024-07-10T22:21:46Z")
This sounds like a regression. Could you please file a bug report in the issue tracker here:
[https://gitlab.kitware.com/cmake/cmake/-/issues/new](https://gitlab.kitware.com/cmake/cmake/-/issues/new)
---
### Author:  [@Sidelobe](https://discourse.cmake.org/u/Sidelobe)
#### Post date: [July 11, 2024, 9:00am UTC](https://discourse.cmake.org/t/cmake-3-30-doesnt-let-me-use-archs-standard-to-set-cmake-osx-architectures/11209/7 "2024-07-11T09:00:22Z")
Thanks for confirming, Craig Scott
I’ve created an issue:
[https://gitlab.kitware.com/cmake/cmake/-/issues/26128](https://gitlab.kitware.com/cmake/cmake/-/issues/26128)