[swift-dev] Glibc.swift: error: no such module 'SwiftGlibc'

[Jordan Rose]

> On Nov 10, 2016, at 13:34, Eric Wing <ewmailing at gmail.com> wrote:
> 
> On 11/9/16, Eric Wing <ewmailing at gmail.com> wrote:
>> On 11/9/16, Eric Wing <ewmailing at gmail.com> wrote:
>>> On 11/9/16, Jordan Rose <jordan_rose at apple.com> wrote:
>>>> Ah, that does help. The logic to build the Glibc module map comes from
>>>> stdlib/public/Platform/CMakeLists.txt, and explicitly checks for
>>>> “LINUX”,
>>>> “FREEBSD”, “ANDROID”, and “CYGWIN”. Does the Steam-Runtime build use a
>>>> different SDK name?
>>>> 
>>>> Jordan
>>>> 
>>> 
>>> How would I verify/debug this for sure? I haven't been setting
>>> anything differently when I build under Steam-Runtime vs. Ubuntu. (And
>>> I have gotten through a pure Linux (no Android) build under
>>> Steam-Runtime successfully.) Steam-Runtime is just a Linux. (It is
>>> originally derived from Ubuntu 12.04LTS, though it probably has all
>>> its Ubuntu identifiers stripped/replaced.)
>>> 
>>> 
>>> I checked the CMakeCache.txt in
>>> build/Ninja-ReleaseAssert/swift-linux-x86_64
>>> 
>>> Both files are identical between the Steam-Runtime and Ubuntu versions
>>> when building for Android. The variable SWIFT_SDKS is:
>>> SWIFT_SDKS:STRING=ANDROID;LINUX
>>> 
>>> 
>>> Obviously something is different somewhere since it seems to be
>>> skipping the glibc.modulemap in the Steam-Runtime case.
>>> 
>>> 
>>> Thanks,
>>> Eric
>>> 
>> 
>> Oops. Correction to my last post. The CMakeCache.txt are not
>> identical. I compared the wrong files.
>> 
>> However, the SWIFT_SDKS variable are the same in each.
>> 
>> Here are some differences I did spot:
>> 
>> In Ubuntu, LIBXML2_XMLLINT_EXECUABLE is not found, but defined in my
>> SteamRT cache.
>> 
>> Ubuntu:
>> SWIFT_HAVE_WORKING_STD_REGEX_TEST:INTERNAL=1
>> Steam
>> SWIFT_HAVE_WORKING_STD_REGEX_TEST:INTERNAL=
>> 
>> Ubuntu:
>> SWIFT_HAVE_WORKING_STD_REGEX_TEST_EXITCODE:INTERNAL=0
>> Steam:
>> SWIFT_HAVE_WORKING_STD_REGEX_TEST_EXITCODE:INTERNAL=FAILED_TO_RUN
>> 
>> 
>> The remaining of the differences are tool version differences and
>> stuff with libICU (because Steam-Runtime doesn't supply it so I must
>> build/supply it myself). But most of these differences are expected.
>> 
>> Thanks,
>> Eric
>> 
> 
> 
> It looks like the problem is related to which version of CMake you use.
> 
> Ubuntu 16.10 supplies CMake 3.5.2.
> Steam-Runtime ships a version that is way too old, so I built and used
> the latest stable CMake version, 3.6.3.
> 
> Using 3.6.3 seems to always trigger this problem with the Swift build.
> 
> I tested it both ways:
> 
> 1. I changed Ubuntu 16.10 to use CMake 3.6.3 and the build broke in
> exactly the same way I described.
> 
> 2. In Steam-Runtime, I built/used CMake 3.5.2 instead, and the build completed.
> 
> 
> I still don’t know specifically what the build script bug is. This is
> going to need to be fixed eventually if all newer versions of CMake
> lead to a broken build process.

Nice job tracking this down! I can’t reproduce it with CMake 3.6.3 on Ubuntu 16.04 with a default configuration, though—or at least, I still see the glibc.modulemap target being generated in the Ninja file and listed as a dependency. Can you include your full build-script invocation line?

Jordan