Memory leak from list<CloneList *>

[Richard Kimberly Heck]

On 2/18/20 6:07 PM, Scott Kostyshak wrote:
> Valgrind gave me the following error:
>
>   ==732== 112 (72 direct, 40 indirect) bytes in 1 blocks are definitely lost in loss record 5,165 of 5,862
>   ==732==    at 0x483AE63: operator new(unsigned long) (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
>   ==732==    by 0x103A62D: lyx::Buffer::cloneBufferOnly() const (Buffer.cpp:661)
>   ==732==    by 0x11E583C: lyx::(anonymous namespace)::copyToTempBuffer(lyx::ParagraphList const&, std::shared_ptr<lyx::DocumentClass const>) (CutAndPaste.cpp:582)
>   ==732==    by 0x11E5C6A: lyx::(anonymous namespace)::putClipboard(lyx::ParagraphList const&, std::shared_ptr<lyx::DocumentClass const>, std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&, lyx::BufferParams) (CutAndPaste.cpp:613)
>   ==732==    by 0x11E910B: lyx::cap::copySelection(lyx::Cursor const&, std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&) (CutAndPaste.cpp:1123)
>   ==732==    by 0x11E84F8: lyx::cap::copySelection(lyx::Cursor const&) (CutAndPaste.cpp:1024)
>   ==732==    by 0x13ECDAB: lyx::Text::dispatch(lyx::Cursor&, lyx::FuncRequest&) (Text3.cpp:1593)
>   ==732==    by 0x1767E04: lyx::InsetText::doDispatch(lyx::Cursor&, lyx::FuncRequest&) (InsetText.cpp:339)
>   ==732==    by 0x15FFC39: lyx::Inset::dispatch(lyx::Cursor&, lyx::FuncRequest&) (Inset.cpp:325)
>   ==732==    by 0x11D1B13: lyx::Cursor::dispatch(lyx::FuncRequest const&) (Cursor.cpp:825)
>   ==732==    by 0x1816F4F: lyx::frontend::GuiView::dispatchToBufferView(lyx::FuncRequest const&, lyx::DispatchResult&) (GuiView.cpp:3878)
>   ==732==    by 0x181B959: lyx::frontend::GuiView::dispatch(lyx::FuncRequest const&, lyx::DispatchResult&) (GuiView.cpp:4569)
>
> It comes from the following line (Buffer.cpp:661):
>
>   cloned_buffers.push_back(new CloneList);
>
> Currently cloned_buffers is a list<CloneList *>. Would it make sense to make it a list of *smart* pointers instead? Alternatively we could make a class and then make a custom destructor that would free the CloneLists that the list elements point to?

This is some kind of thinko, probably on my part. The code at line 549
was supposed to be cleaning this up, but it actually only removes the
entry from the list.

If it works to make it a smart pointer of some kind, then that would be
simplest. But I think we could just do something like:

else {
    delete(*it);
    cloned_buffers.erase(it);
}

I should learn how to use valgrind. Then I could solve these problems
myself....

Riki