Fix UB in CPU_tensor_apply#13121
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std::memcpy has UB when either of src or dest are NULL, even if length is 0. This can and does happen when the input tensors are scalar tensors. This triggered UBSAN on pytorch#12824 but it is strange that it has not been triggered before. Test Plan: wait for tests
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Summary: std::memcpy has UB when either of src or dest are NULL, even if length is 0. This can and does happen when the input tensors are scalar tensors. This triggered UBSAN on #12824 but it is strange that it has not been triggered before. Pull Request resolved: pytorch/pytorch#13121 Differential Revision: D10853113 Pulled By: zou3519 fbshipit-source-id: c4b4ad5e41de6f73dc755e0c25bc9947576a742d
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Summary: std::memcpy has UB when either of src or dest are NULL, even if length is 0. This can and does happen when the input tensors are scalar tensors. This triggered UBSAN on pytorch#12824 but it is strange that it has not been triggered before. Pull Request resolved: pytorch#13121 Differential Revision: D10853113 Pulled By: zou3519 fbshipit-source-id: c4b4ad5e41de6f73dc755e0c25bc9947576a742d
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std::memcpy has UB when either of src or dest are NULL, even if length
is 0. This can and does happen when the input tensors are scalar tensors.
This triggered UBSAN on #12824 but it is strange that it has not
been triggered before.
Test Plan: wait for tests