https://issues.dlang.org/show_bug.cgi?id=23953

          Issue ID: 23953
           Summary: Windows. import path contains not all files
           Product: D
           Version: D2
          Hardware: All
                OS: Windows
            Status: NEW
          Severity: major
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: black80@bk.ru

I faced up with issues:
(dmd2)\windows\bin64\..\..\src\druntime\import\object.d-mixin-4744(4744,19):
Error: unable to read module `sync`
(dmd2)\windows\bin64\..\..\src\druntime\import\object.d-mixin-4744(4744,19):
    Expected 'core\sync.d' or 'core\sync\package.d' in one of the following
import paths:
import path[0] = source
import path[1] = (dmd2)\windows\bin64\..\..\src\phobos
import path[2] = (dmd2)\windows\bin64\..\..\src\druntime\import

and u can see in
https://downloads.dlang.org/pre-releases/2.x/2.104.0/dmd.2.104.0-rc.1.windows.7z
(2.103.1 same) that folder "src\druntime\import" doesn't contain
"core/sync/package.d".
but folder "src\druntime\src" contains the one.

so workaround copy the one from one folder to other.

need to fix:
1) deal with import files/folder.
2) try to get rid of duplicate files (just increase the archive).

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