Compilation error on gcc 12: pointer used after ‘void operator delete(void*, std::size_t)’

[kpu]

Marian doesn't compile with gcc 12.3.1 due to issues with intrusive pointer. Note that there are two kinds of error: pointer used after and pointer may be used. It would seem in the first error that the compiler is definitely finding an issue.

gcc --version
gcc (Gentoo 12.3.1_p20230526 p2) 12.3.1 20230526
Copyright (C) 2022 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

In file included from /home/kpu/marian-dev/src/common/definitions.h:5,
                 from /home/kpu/marian-dev/src/tensors/tensor.h:3,
                 from /home/kpu/marian-dev/src/optimizers/clippers.h:6,
                 from /home/kpu/marian-dev/src/optimizers/clippers.cpp:1:
In function ‘void marian::intrusivePtrRelease(TensorBase*)’,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘virtual float marian::ElementwiseClipper::clip(marian::Tensor, float)’ at /home/kpu/marian-dev/src/optimizers/clippers.cpp:9:10:
/home/kpu/marian-dev/src/common/intrusive_ptr.h:24:23: error: pointer used after ‘void operator delete(void*, std::size_t)’ [-Werror=use-after-free]
   24 |     if(x != 0 && --x->references_ == 0) {    \
      |                    ~~~^~~~~~~~~~~
/home/kpu/marian-dev/src/tensors/tensor.h:38:3: note: in expansion of macro ‘ENABLE_INTRUSIVE_PTR’
   38 |   ENABLE_INTRUSIVE_PTR(TensorBase)
      |   ^~~~~~~~~~~~~~~~~~~~
In destructor ‘virtual marian::TensorBase::~TensorBase()’,
    inlined from ‘void marian::intrusivePtrRelease(TensorBase*)’ at /home/kpu/marian-dev/src/tensors/tensor.h:38:3,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::Element(Functor, Tensor, Tensors ...) [with Functor = functional::Assign<functional::Var<1>, functional::BinaryFunctor<functional::elem::Clip, functional::Assignee<1>, functional::Capture> >; Tensors = {}]’ at /home/kpu/marian-dev/src/tensors/tensor_operators.h:75:17,
    inlined from ‘virtual float marian::ElementwiseClipper::clip(marian::Tensor, float)’ at /home/kpu/marian-dev/src/optimizers/clippers.cpp:9:10:
/home/kpu/marian-dev/src/tensors/tensor.h:76:26: note: call to ‘void operator delete(void*, std::size_t)’ here
   76 |   virtual ~TensorBase() {}
      |                          ^
cc1plus: all warnings being treated as errors
make[2]: *** [src/CMakeFiles/marian.dir/build.make:958: src/CMakeFiles/marian.dir/optimizers/clippers.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
In file included from /home/kpu/marian-dev/src/common/definitions.h:5,
                 from /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:1:
In function ‘void marian::intrusivePtrRelease(TensorBase*)’,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::ExponentialSmoothing::updateAvgParams(marian::Tensor, marian::Tensor, size_t, size_t)’ at /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:24:10:
/home/kpu/marian-dev/src/common/intrusive_ptr.h:24:23: error: pointer may be used after ‘void operator delete(void*, std::size_t)’ [-Werror=use-after-free]
   24 |     if(x != 0 && --x->references_ == 0) {    \
      |                    ~~~^~~~~~~~~~~
/home/kpu/marian-dev/src/tensors/tensor.h:38:3: note: in expansion of macro ‘ENABLE_INTRUSIVE_PTR’
   38 |   ENABLE_INTRUSIVE_PTR(TensorBase)
      |   ^~~~~~~~~~~~~~~~~~~~
In file included from /home/kpu/marian-dev/src/tensors/tensor_operators.h:5,
                 from /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:3:
In destructor ‘virtual marian::TensorBase::~TensorBase()’,
    inlined from ‘void marian::intrusivePtrRelease(TensorBase*)’ at /home/kpu/marian-dev/src/tensors/tensor.h:38:3,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::Element(Functor, Tensor, Tensors ...) [with Functor = functional::Assign<functional::Var<1>, functional::BinaryFunctor<functional::elem::Plus, functional::BinaryFunctor<functional::elem::Mult, functional::Capture, functional::Assignee<1> >, functional::BinaryFunctor<functional::elem::Mult, functional::Capture, functional::Assignee<2> > > >; Tensors = {IntrusivePtr<TensorBase>}]’ at /home/kpu/marian-dev/src/tensors/tensor_operators.h:75:17,
    inlined from ‘void marian::ExponentialSmoothing::updateAvgParams(marian::Tensor, marian::Tensor, size_t, size_t)’ at /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:24:10:
/home/kpu/marian-dev/src/tensors/tensor.h:76:26: note: call to ‘void operator delete(void*, std::size_t)’ here
   76 |   virtual ~TensorBase() {}
      |                          ^
In function ‘void marian::intrusivePtrRelease(TensorBase*)’,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::ExponentialSmoothing::updateAvgParams(marian::Tensor, marian::Tensor, size_t, size_t)’ at /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:24:10:
/home/kpu/marian-dev/src/common/intrusive_ptr.h:24:23: error: pointer may be used after ‘void operator delete(void*, std::size_t)’ [-Werror=use-after-free]
   24 |     if(x != 0 && --x->references_ == 0) {    \
      |                    ~~~^~~~~~~~~~~
/home/kpu/marian-dev/src/tensors/tensor.h:38:3: note: in expansion of macro ‘ENABLE_INTRUSIVE_PTR’
   38 |   ENABLE_INTRUSIVE_PTR(TensorBase)
      |   ^~~~~~~~~~~~~~~~~~~~
In destructor ‘virtual marian::TensorBase::~TensorBase()’,
    inlined from ‘void marian::intrusivePtrRelease(TensorBase*)’ at /home/kpu/marian-dev/src/tensors/tensor.h:38:3,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::Element(Functor, Tensor, Tensors ...) [with Functor = functional::Assign<functional::Var<1>, functional::BinaryFunctor<functional::elem::Plus, functional::BinaryFunctor<functional::elem::Mult, functional::Capture, functional::Assignee<1> >, functional::BinaryFunctor<functional::elem::Mult, functional::Capture, functional::Assignee<2> > > >; Tensors = {IntrusivePtr<TensorBase>}]’ at /home/kpu/marian-dev/src/tensors/tensor_operators.h:75:17,
    inlined from ‘void marian::ExponentialSmoothing::updateAvgParams(marian::Tensor, marian::Tensor, size_t, size_t)’ at /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:24:10:
/home/kpu/marian-dev/src/tensors/tensor.h:76:26: note: call to ‘void operator delete(void*, std::size_t)’ here
   76 |   virtual ~TensorBase() {}
      |                          ^
In function ‘void marian::intrusivePtrRelease(TensorBase*)’,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::ExponentialSmoothing::updateAvgParams(marian::Tensor, marian::Tensor, size_t, size_t)’ at /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:24:10:
/home/kpu/marian-dev/src/common/intrusive_ptr.h:24:23: error: pointer may be used after ‘void operator delete(void*, std::size_t)’ [-Werror=use-after-free]
   24 |     if(x != 0 && --x->references_ == 0) {    \
      |                    ~~~^~~~~~~~~~~
/home/kpu/marian-dev/src/tensors/tensor.h:38:3: note: in expansion of macro ‘ENABLE_INTRUSIVE_PTR’
   38 |   ENABLE_INTRUSIVE_PTR(TensorBase)
      |   ^~~~~~~~~~~~~~~~~~~~
In destructor ‘virtual marian::TensorBase::~TensorBase()’,
    inlined from ‘void marian::intrusivePtrRelease(TensorBase*)’ at /home/kpu/marian-dev/src/tensors/tensor.h:38:3,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::Element(Functor, Tensor, Tensors ...) [with Functor = functional::Assign<functional::Var<1>, functional::BinaryFunctor<functional::elem::Plus, functional::BinaryFunctor<functional::elem::Mult, functional::Capture, functional::Assignee<1> >, functional::BinaryFunctor<functional::elem::Mult, functional::Capture, functional::Assignee<2> > > >; Tensors = {IntrusivePtr<TensorBase>}]’ at /home/kpu/marian-dev/src/tensors/tensor_operators.h:75:17,
    inlined from ‘void marian::ExponentialSmoothing::updateAvgParams(marian::Tensor, marian::Tensor, size_t, size_t)’ at /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:24:10:
/home/kpu/marian-dev/src/tensors/tensor.h:76:26: note: call to ‘void operator delete(void*, std::size_t)’ here
   76 |   virtual ~TensorBase() {}
      |                          ^
In function ‘void marian::intrusivePtrRelease(TensorBase*)’,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::ExponentialSmoothing::updateAvgParams(marian::Tensor, marian::Tensor, size_t, size_t)’ at /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:24:10:
/home/kpu/marian-dev/src/common/intrusive_ptr.h:24:23: error: pointer may be used after ‘void operator delete(void*, std::size_t)’ [-Werror=use-after-free]
   24 |     if(x != 0 && --x->references_ == 0) {    \
      |                    ~~~^~~~~~~~~~~
/home/kpu/marian-dev/src/tensors/tensor.h:38:3: note: in expansion of macro ‘ENABLE_INTRUSIVE_PTR’
   38 |   ENABLE_INTRUSIVE_PTR(TensorBase)
      |   ^~~~~~~~~~~~~~~~~~~~
In destructor ‘virtual marian::TensorBase::~TensorBase()’,
    inlined from ‘void marian::intrusivePtrRelease(TensorBase*)’ at /home/kpu/marian-dev/src/tensors/tensor.h:38:3,
    inlined from ‘IntrusivePtr<T>::~IntrusivePtr() [with T = marian::TensorBase]’ at /home/kpu/marian-dev/src/common/intrusive_ptr.h:66:26,
    inlined from ‘void marian::Element(Functor, Tensor, Tensors ...) [with Functor = functional::Assign<functional::Var<1>, functional::BinaryFunctor<functional::elem::Plus, functional::BinaryFunctor<functional::elem::Mult, functional::Capture, functional::Assignee<1> >, functional::BinaryFunctor<functional::elem::Mult, functional::Capture, functional::Assignee<2> > > >; Tensors = {IntrusivePtr<TensorBase>}]’ at /home/kpu/marian-dev/src/tensors/tensor_operators.h:75:17,
    inlined from ‘void marian::ExponentialSmoothing::updateAvgParams(marian::Tensor, marian::Tensor, size_t, size_t)’ at /home/kpu/marian-dev/src/optimizers/exponential_smoothing.cpp:24:10:
/home/kpu/marian-dev/src/tensors/tensor.h:76:26: note: call to ‘void operator delete(void*, std::size_t)’ here
   76 |   virtual ~TensorBase() {}
      |                          ^
cc1plus: all warnings being treated as errors
make[2]: *** [src/CMakeFiles/marian.dir/build.make:986: src/CMakeFiles/marian.dir/optimizers/exponential_smoothing.cpp.o] Error 1

I've been trying to suss this out. It seems to be the temporary Tensor (i.e. an intrusive_ptr) is having the issue.