[bug] CMAKE_SYSTEM_NAME is set to Darwin on iOS (watch and tv OS)

[a4z]

Coming from here, #4550 I can see that the change was not enough.

The CMAKE_SYSTEM_NAME is always set to Darwin, even for iOS (cross) builds, what is wrong

please check
https://cmake.org/cmake/help/latest/manual/cmake-toolchains.7.html#cross-compiling-for-ios-tvos-or-watchos
that clearly specifies what should be used

and for example the help to the cmake IOS variable
https://cmake.org/cmake/help/latest/variable/IOS.html

Set to 1 when the target system (CMAKE_SYSTEM_NAME) is iOS

clearly, setting this to Darwin for iOS is not good.

Environment Details (include every applicable attribute)

• Operating System+version: OSX 10.15.7
• Compiler+version: apple clang 12
• Conan version: 1.30.1
• Python version: 3.8.5

[jgsogo]

We modified it here (#7827) but didn't change the values you are referring to. I think @czoido can help here, he is having to Conan toolchains for iOS.

[a4z]

if you want to build for iOS there is also this PR
conan-io/conan-center-index#1137

[czoido]

Yes, I think those should be changed to the corresponding platform since CMake 3.14+ has native support setting CMAKE_SYSTEM_NAME with iOS, tvOS, or watchOS.

[memsharded]

Yes, I think those should be changed to the corresponding platform since CMake 3.14+ has native support setting CMAKE_SYSTEM_NAME with iOS, tvOS, or watchOS.

Please keep in mind that there are Conan users with versions lower than CMake 3.14, and this change shouldn't break them

[czoido]

Hi @a4z,

I have opened a PR to fix this issue assigned to Conan 1.31: #7924

[a4z]

Thanks, looks good!
Of course, I do not know what happens for cmake > 3.14 users, if they try to use the cmake-ios toolchain, but I think I am not interested to find out, they shall update cmake in this case , what makes sense.