[Backport 2.28] mbedtls_mpi_sub_abs: Skip memcpy when redundant (#6701). #7001
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
In some contexts, the output pointer may equal the first input pointer, in which case copying is not only superfluous but results in "Source and destination overlap in memcpy" errors from Valgrind (as I observed in the context of ecp_double_jac) and a diagnostic message from TrustInSoft Analyzer (as Pascal Cuoq reported in the context of other ECP functions called by cert-app with a suitable certificate).
Signed-off-by: Aaron M. Ucko ucko@ncbi.nlm.nih.gov
Description
Backport of #6942.
Gatekeeper checklist
Notes for the submitter
Please refer to the contributing guidelines, especially the
checklist for PR contributors.