ARROW-3860: [WIP][Gandiva][C++] Link std c++ statically.

[praveenbingo]

Restores linking statically to std c++, so that it can be safely packaged for other
similar environments.

[pitrou]

I'm not sure we want to do that by default. @wesm

[wesm]

-1. Use CMAKE_SHARED_LINKER_FLAGS when invoking CMake

[jacques-n]

Hey @wesm, apparently the changes these are trying to revert to Gandiva mean we've broken the downstream Dremio builds. We should try to avoid making changes that break downstream builds without alternative paths already in place. It seems like the original change this is reverting broke a pattern without a proper alternative available.

[wesm]

I hear you -- this issue is a bit distressing as the hard-coding of linker flags specific to Dremio builds was causing problems for other Arrow developers. I asked multiple times and waited over a month before fixing the problem myself

• October 4: ARROW-3331: [Gandiva][C++] Add re2 to toolchain #2695 (comment)
• October 6: ARROW-3382: [Gandiva][C++] Run tests in travis #2705 (comment)
• October 11: ARROW-3442: [C++] Allow dynamic linking of (most) unit tests #2744 (comment)
• November 10, raising ARROW-3437 to blocker: https://issues.apache.org/jira/browse/ARROW-3437?focusedCommentId=16682681&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-16682681

Here is the fix on November 19: ba2b2ea#diff-55d595f15416efb8fd2b661f37cb55b7

We have a problem of process right now in that people like me are not able to verify changes that are affecting Dremio builds -- had I been able to, I would have been glad to sort out a remediation. Short of that, I am not sure how else I would have been able to force action on this issue. As you can see in the discussion on https://issues.apache.org/jira/browse/ARROW-3860, there is a lack of transparency into your process that makes it difficult for me to help.

[wesm]

If you want to revert ba2b2ea temporarily until you figure out the packaging stuff, it's fine with me, but let's please not let it linger much longer since I would like to get the project into release-ready shape in the next 2-3 weeks

[wesm]

I think #3035 will address the issue

[jacques-n]

Hey @wesm , I appreciate your attention and detailed response. I've opened up https://issues.apache.org/jira/browse/ARROW-3887 and will have our team work on adding that. There is no desire to be opaque. Will work with the team on becoming more transparent as well.

[praveenbingo]

Thanks a ton Wes and Jacques for taking this to closure.