https://issues.dlang.org/show_bug.cgi?id=21053

          Issue ID: 21053
           Summary: Test Suite run.d is built with compiler under test,
                    must be build with bootstrap dmd
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: blocker
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

The reason is because of this clip from the autotester log file:

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/home/braddr/sandbox/at-client/pull-4118165-Linux_32/dmd/generated/linux/release/32/dmd
-conf= -m32  -g -odgenerated -ofgenerated/run -i -release run.d
generated/run --environment runnable compilable fail_compilation dshell
Makefile:210: recipe for target 'auto-tester-test' failed
make[1]: *** [auto-tester-test] Segmentation fault (core dumped)
-----------

It appears that run.d is itself seg faulting. The tests in test/runnable are there to debug the compiler BEFORE anything else is compiled. That's because those are designed to debug the compiler with. This is all defeated if the run.d doesn't function because it was built with a buggy compiler.

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