git clone and Launchpad build system

[Joseph Rushton Wakeling]

On 18/03/17 21:28, Joseph Rushton Wakeling wrote:
> On 18/03/17 14:46, Joseph Rushton Wakeling wrote:
>> Is there an issue with using git source for parts of snap packages when using
>> the Launchpad build system?  I'm having consistent build failures for this;
>> originally I tried switching from `git://` URLS to `https://`, but I'm still
>> seeing the same errors, see e.g.
>> https://launchpadlibrarian.net/311390659/buildlog_snap_ubuntu_xenial_amd64_ldc2_BUILDING.txt.gz:
>>
>
> Still failing despite updating to make sure the `source-type` is explicitly
> specified as git.  The same snap package builds fine for me with a `snapcraft
> cleanbuild`.

A look a bit further back in the build log reveals what I think may be the 
problem: the submodules of one of the git repositories have their URLs specified 
using `git://` URLs:

Submodule 'druntime' (git://github.com/ldc-developers/druntime.git) registered 
for path 'runtime/druntime'
Submodule 'phobos' (git://github.com/ldc-developers/phobos.git) registered for 
path 'runtime/phobos'
Submodule 'tests/d2/dmd-testsuite' 
(git://github.com/ldc-developers/dmd-testsuite.git) registered for path 
'tests/d2/dmd-testsuite'
Cloning into 'runtime/druntime'...
fatal: unable to connect to github.com:
github.com: Name or service not known

fatal: clone of 'git://github.com/ldc-developers/druntime.git' into submodule 
path 'runtime/druntime' failed

Are `git://` URLS genuinely not supported by the launchpad build system?  And if 
so, is there a chance this could be addressed?