[Issue 21294] [REG 2.095]: DMD fails to link since PR11743

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=21294

--- Comment #6 from Iain Buclaw <ibuclaw at gdcproject.org> ---
Slightly tweaked for some added parallelism for bisecting dmd.  I'll see if
there's a first good commit with dmd.

```
#!/bin/bash

if [ -d build ]; then rm -r build; fi
mkdir build
echo "/etc" > build/SYSCONFDIR.imp
echo "v2.000.0" > build/VERSION

for dir in . root backend; do
    mkdir -p build/${dir}
    for src in src/dmd/${dir}/*.d; do
        echo dmd -version=MARS -I=src -J=src/dmd/res -J=build \
            -c -od=build/${dir} ${src}
        dmd -version=MARS -I=src -J=src/dmd/res -J=build \
            -c -od=build/${dir} ${src} &
        sleep 0.05
    done
done

echo dmd build/*.o build/root/*.o build/backend/*.o -of=build/dmd
dmd build/*.o build/root/*.o build/backend/*.o -of=build/dmd

echo =========================
dmd --version

--