https://issues.dlang.org/show_bug.cgi?id=19805

          Issue ID: 19805
           Summary: wrong windows mangling for generic arguments with two
                    identical template args
           Product: D
           Version: D2
          Hardware: All
                OS: Windows
            Status: NEW
          Severity: blocker
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: ilyayaroshenko@gmail.com

C++
==================================
template<class T, class T> struct C {};
template<class T> struct R {};

void bar3(C<int*, int*>) {}
void bar4(C<R<int>, R<int>>) {}

// ?bar3@@YAXU?$C@PEAHPEAH@@@Z
// ?bar4@@YAXU?$C@U?$R@H@@U1@@@@Z
==================================

D
==================================
struct C(T1, T2) {}
struct R(T) {}

extern(C++):

void bar3(C!(int*, int*));
void bar4(C!(R!int, R!int));

pragma(msg, bar3.mangleof);
pragma(msg, bar4.mangleof);

// ?bar3@@YAXU?$C@PEAH0@@@Z (wrong)
// ?bar4@@YAXU?$C@U?$R@H@@0@@@Z (wrong)
==================================

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