https://issues.dlang.org/show_bug.cgi?id=21119

          Issue ID: 21119
           Summary: Code coverage checker is not instrumenting backend
                    source files
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dlang.org
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

For example,

https://codecov.io/gh/dlang/dmd/src/master/src/dmd/backend/cod4.d

shows 0% coverage.

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