Fix Issue 20618 - std.random.unpredictableSeed can work in betterC

[n8sh]

The diff is easier to review with whitespace changes hidden.

[dlang-bot]

Thanks for your pull request, @n8sh!

Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20618	enhancement	std.random.unpredictableSeed can work in betterC

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + phobos#7408"

[n8sh]

At least on my machine the @betterC test extractor doesn't seem to be running any tests (it always succeeds). I manually tested this locally but this probably shouldn't be merged unless or until automatic tests are working properly.

[n8sh]

On my machine changing this function to a template was necessary to avoid a symbol not found error with betterC. This seems like a bug.

[kinke]

Why would that be a bug? Everything that works in betterC must be templated (or inlined), as druntime and Phobos aren't linked. So of course we could needlessly templatize most of druntime, but what would be the point? Static functionality that can be precompiled once for many compilation cycles does provide benefits.

[n8sh]

I misunderstood how betterC treats Phobos then. I thought it treated it like any library.

[wilzbach]

At least on my machine the @betterC test extractor doesn't seem to be running any tests (it always succeeds). I manually tested this locally but this probably shouldn't be merged unless or until automatic tests are working properly.

Good catch! -> #7409

[n8sh]

#7408 (comment)

So of course we could needlessly templatize most of druntime, but what would be the point? Static functionality that can be precompiled once for many compilation cycles does provide benefits.

Closing because I now have doubts about whether this PR is a net improvement.