fix bugzilla Issue 24819 - Optimizer changes result of float calculat…

[veelo]

…ions on 32-bit

Cherry picked from master.

[dlang-bot]

Thanks for your pull request and interest in making D better, @veelo! We are looking forward to reviewing it, and you should be hearing from a maintainer soon.
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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	24819	major	Optimizer changes result of float calculations on 32-bit

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 "stable + dmd#17028"