fix: memory leak in dal::homogen_table to ndarray conversion

[Vika-F]

Description

Add a comprehensive description of proposed changes

List associated issue number(s) if exist(s): #6 (for example)

Documentation PR (if needed): #1340 (for example)

Benchmarks PR (if needed): IntelPython/scikit-learn_bench#155 (for example)

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[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 3 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
onedal/datatypes/numpy/data_conversion.cpp	50.00%	0 Missing and 2 partials ⚠️
onedal/datatypes/table.cpp	50.00%	0 Missing and 1 partial ⚠️

Flag	Coverage Δ
azure	79.93% <ø> (?)
github	71.67% <50.00%> (?)

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Files with missing lines	Coverage Δ
onedal/datatypes/table.cpp	52.94% <50.00%> (ø)
onedal/datatypes/numpy/data_conversion.cpp	53.02% <50.00%> (ø)

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[icfaust]

would this also be a memory leak by the typing change for the array in this PR? https://github.com/uxlfoundation/scikit-learn-intelex/blob/main/onedal/datatypes/dlpack/data_conversion.cpp#L242

[david-cortes-intel]

I think the resetting part is not strictly needed.

At least according to ASAN, there's no leak from the arrays allocated by SVMs after the similar changes in this PR which do not involve resetting:
#2540

[icfaust]

I think the resetting part is not strictly needed.

At least according to ASAN, there's no leak from the arrays allocated by SVMs after the similar changes in this PR which do not involve resetting: #2540

Totally onboard with that, just have a niggling worry that I am missing something about get_original_data that isn't being covered by ASan/ maybe should be addressed by documentation on oneDAL-side.

[Vika-F]

@icfaust

would this also be a memory leak by the typing change for the array in this PR? https://github.com/uxlfoundation/scikit-learn-intelex/blob/main/onedal/datatypes/dlpack/data_conversion.cpp#L242

I do not see the typing change here.
Is my understanding correct, the array is created here as array<byte_t>:
https://github.com/uxlfoundation/scikit-learn-intelex/blob/main/onedal/datatypes/dlpack/data_conversion.cpp#L230
?

And it is deleted as array<byte_t>. It is Ok.

What is not Ok, is to create an array<X> and destroy it as an array<Y>. As those are two different classes.

[david-cortes-intel]

I think the resetting part is not strictly needed.
At least according to ASAN, there's no leak from the arrays allocated by SVMs after the similar changes in this PR which do not involve resetting: #2540

Totally onboard with that, just have a niggling worry that I am missing something about get_original_data that isn't being covered by ASan/ maybe should be addressed by documentation on oneDAL-side.

Have you tried asan with something executing that codepath? Do you have some small snippet to execute that would trigger the code from that file?

[Vika-F]

@david-cortes-intel @icfaust
I was thinking that in #2540 the array is created as array<byte_t> and destroyed as array<T> where T != byte_t.
That understanding was incorrect, sorry.

Now I see that the array is created and destroyed as array<byte_t>.
So #2540 solves the issue with less amount of code changes. I am closing this one.