Issue 21488 - Always compile phobos library with -fPIC on POSIX targets

[ibuclaw]

Segmentation faults or linker errors occur on 32-bit PIE platforms if any object is not compiled with -fPIC.

[dlang-bot]

Thanks for your pull request, @ibuclaw!

Bugzilla references

Auto-close	Bugzilla	Severity	Description
✗	21488	normal	Bundled 32-bit dlang tools (ddemangle, dustmite, rdmd) segfault on startup

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 + phobos#8154"

[ibuclaw]

Ping @MartinNowak don't know if you need to fix your release build scripts.