https://issues.dlang.org/show_bug.cgi?id=23889

          Issue ID: 23889
           Summary: ImportC: alloca() not supported
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

As reported by Patrick Schluter:

Even replacing VLA with alloca() does not work/
Error: undefined identifier `__builtin_alloca`

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