Win32AttachOperationRequest seems to be using global new?

[Julian Waters]

Hi all,

Win32AttachOperationRequest is created via new, but doesn't specify a
custom new inside the class definition. The result seems to be that we use
global new on Windows:

  for (int i=0; i<max_enqueued_operations; i++) {
    Win32AttachOperationRequest* op = new Win32AttachOperationRequest();
      f1: b9 28 0d 00 00       mov    ecx,0xd28
      f6: e8 00 00 00 00       call   fb <Win32AttachListener::init()+0x7b>
f7: IMAGE_REL_AMD64_REL32 operator new(unsigned long long)

Stepping away from gcc's objdump and using the Microsoft dumpbin alongside
cl.exe instead, the result is this:

  0000000000000264: B9 28 0D 00 00     mov         ecx,0D28h
  0000000000000269: E8 00 00 00 00     call        ??2 at YAPEAX_K@Z
  000000000000026E: 48 89 44 24 28     mov         qword ptr [rsp+28h],rax
  0000000000000273: 48 83 7C 24 28 00  cmp         qword ptr [rsp+28h],0
  0000000000000279: 74 11              je          000000000000028C
  000000000000027B: 48 8B 4C 24 28     mov         rcx,qword ptr [rsp+28h]
  0000000000000280: E8 00 00 00 00     call
 ??0Win32AttachOperationRequest@@QEAA at XZ

undname "??2 at YAPEAX_K@Z"
Microsoft (R) C++ Name Undecorator
Copyright (C) Microsoft Corporation. All rights reserved.

Undecoration of :- "??2 at YAPEAX_K@Z"
is :- "void * __ptr64 __cdecl operator new(unsigned __int64)"

undname "??0Win32AttachOperationRequest@@QEAA at XZ"
Microsoft (R) C++ Name Undecorator
Copyright (C) Microsoft Corporation. All rights reserved.

Undecoration of :- "??0Win32AttachOperationRequest@@QEAA at XZ"
is :- "public: __cdecl
Win32AttachOperationRequest::Win32AttachOperationRequest(void) __ptr64"

Visual Studio, lacking the nm utility, obviously doesn't catch this. What
was more surprising is that the gcc Link Time check also fails to catch it
as well. I had to manually check the output of nm after an unrelated
failure and happened to stumble across the symbols _Znwy and _ZdlPvy which
both correspond to

operator new(unsigned long long)
operator delete(void*, unsigned long long)

The delete can be ignored, it's the result of a bug on my experimental
branch (It was first discovered there, then I tested it on master). I'm
more interested about the new, since it seems to be violating a HotSpot
rule. Is this an intentional exception to the rule, or an oversight?

best regards,
Julian
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