[Issue 17504] New: Passing templated varargs to array varargs base class constructor segfaults

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=17504

          Issue ID: 17504
           Summary: Passing templated varargs to array varargs base class
                    constructor segfaults
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: minor
          Priority: P1
         Component: druntime
          Assignee: nobody at puremagic.com
          Reporter: nanayamae at gmail.com

Created attachment 1649
  --> https://issues.dlang.org/attachment.cgi?id=1649&action=edit
Reduction of the segfault

I have a templated wrapper class (TC) that inherits from its template argument.
The base class's (BC) constructor arguments are unknown, therefore the
constructor of TC is templated with 
this(Args...)(MyType wrappedObj, Args args)
{
    super(args);
}
and calls its base constructor using args.
When the base constructor has varargs 
this(MyType[] objs...)
{
    _objs = objs;
} 
and TC's templated constructor is called using varargs 
auto tc = new TC(wrappedObj, obj1, obj2); // segfaults
any attempt at accessing the objects in _objs by iterating (std.algorithm or
foreach) segfaults (see attachment). Calling _objs[0] and accessing its members
is ok.
A workaround is passing in an array instead of varargs, therefore marked as
minor.
auto tc = new TC(wrappedObj, [obj1, obj2]); // ok
The full code is in attachment.

(Please forgive me if I mixed up a bit of terminology.)

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