test: check @tagName() in callconv C function

This is a regression test for an x86_64 backend miscompilation when
using @tagName() in a callconv(.c) function with -fPIC.
87bbb49d5fIsaac Freund committed on 2/7/2025, 6:20:53 AMparent043e3b2
1 file changedLine totals unavailable