Fix cmake build on MacOS

[nickwanninger]

I get this error on every single file that the CMake program attempts to compile. Is this a known problem or is my machine not configured correctly?

In file included from /var/folders/33/mjfjj83j3zgc_hfnrkj9wkjw0000gn/T/tmp.HMPg99oq/bdwgc/alloc.c:19:
In file included from /var/folders/33/mjfjj83j3zgc_hfnrkj9wkjw0000gn/T/tmp.HMPg99oq/bdwgc/include/private/gc_priv.h:59:
In file included from /usr/include/stdlib.h:65:
In file included from /usr/include/sys/wait.h:109:
In file included from /usr/include/sys/signal.h:150:
In file included from /usr/include/sys/_types/_sigaltstack.h:40:
/usr/include/machine/types.h:37:2: error: architecture not supported
#error architecture not supported
 ^

[ivmai]

CMake works on Windows. Should work on other hosts but not tested for ages. The script contains some workaround for MacOS:

IF(APPLE)
    IF("${CMAKE_OSX_ARCHITECTURES}" STREQUAL "")
        SET(CMAKE_OSX_ARCHITECTURES "ppc;i386;x86_64" CACHE STRING "Build architectures for Mac OS X" FORCE)
    ENDIF()
ENDIF(APPLE)

I guess it should not be difficult to fix the build.

[nickwanninger]

Hmm, I've looked into this and the only way I can get it working is by a) moving that workaround to above the project() call, and b) changing the architectures to only "x86_64".

IF(APPLE)
    IF("${CMAKE_OSX_ARCHITECTURES}" STREQUAL "")
        SET(CMAKE_OSX_ARCHITECTURES "x86_64" CACHE STRING "Build architectures for Mac OS X" FORCE)
    ENDIF()
ENDIF(APPLE)

Doing this allows me to fully compile using cmake on macos. Or I can call CMake with cmake .. -DCMAKE_OSX_ARCHITECTURES=x86_64 on macos

[ivmai]

If you know how to fix this in GC, please contribute.

[vicroms]

@nickwanninger

I've opened a PR (#281) to modify the existing CMakeLists.txt, which I believe is due for modernization.

I'll try to add your workaround there as well.

[vicroms]

Hi @nickwanninger
It's been a while, but can you test whether the patches in PR #281 work for you?

[nickwanninger]

Yes I will look into the PR really quick

[nickwanninger]

@vicroms, #281 doesn't seem to work for me. I simply did a mkdir build; cd build; cmake ..; make and it fails on the final make with the same error as it did before

[vicroms]

I see, I'll try to get a Mac to make some more local testing.
Thanks @nickwanninger!

[nickwanninger]

Ill see what I can figure out as well

[nickwanninger]

@vicroms. So it seems that running cmake with cmake .. -DCMAKE_OSX_ARCHITECTURES=x86_64 allows builds on macos in your PR

[ivmai]

I've looked into this and the only way I can get it working is by a) moving that workaround to above the project() call, and b) changing the architectures to only "x86_64".

@nickwanninger moving that workaround to above the project() is not needed, right?

[nickwanninger]

It seems like it. I was able to just run with that flag on @vicroms' PR with no modifications

Is there a way to add that flag into the cmakelist?

[ivmai]

Hello @nickwanninger, @vicroms,
I have modified the cmake script in the master branch since this discussion, e.g. multi-threaded builds are on by default now. It would be nice if you test the latest version if it works OK for you.