https://issues.dlang.org/show_bug.cgi?id=16151

          Issue ID: 16151
           Summary: duplicate symbol
                    _D4core4sync5mutex5Mutex12MonitorProxy6__initZ in:
           Product: D
           Version: D2
          Hardware: x86
                OS: Mac OS X
            Status: NEW
          Severity: regression
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: timothee.cour2@gmail.com

this regression is hard to minimize but I'm getting with DMD64 D Compiler v2.071.0 (dmd from homebrew)

duplicate symbol _D4core4sync5mutex5Mutex12MonitorProxy6__initZ in:
    /tmp/.rdmd-501/rdmd-project_run.d-XXX/z01.o
    ~/homebrew/lib//libphobos2.a(mutex_39c_213.o)
ld: 1 duplicate symbol for architecture x86_64

which corresponds to: core.sync.mutex.Mutex.MonitorProxy.__init

this was after an invocation of rdmd (ie of dmd...)

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