Jim Apple has posted comments on this change. ( http://gerrit.cloudera.org:8080/11406 )
Change subject: IMPALA-5031: undefined behavior: codegen signed overflow ...................................................................... Patch Set 2: (2 comments) http://gerrit.cloudera.org:8080/#/c/11406/1/be/src/exprs/operators-ir.cc File be/src/exprs/operators-ir.cc: http://gerrit.cloudera.org:8080/#/c/11406/1/be/src/exprs/operators-ir.cc@56 PS1, Line 56: converted to a prvalue of another integer type. ... If the destination type is > did you verify that it's happening? what about in debug builds? I can see that it's happening in release. In debug, this still generates a few unnecessary IR loads/stores, but no actual calls to memcpy. Good suggestion about the static cast. A static cast works correctly TO unsigned, but not FROM, I learned, so this new patchset still has one memcpy. http://gerrit.cloudera.org:8080/#/c/11406/1/be/src/exprs/operators-ir.cc@65 PS1, Line 65: docs p > the std:: doesn't seem necessary If we #include <string.h>, I agree, but I think cstring puts it in std::, not ::. https://en.cppreference.com/w/cpp/string/byte/memcpy -- To view, visit http://gerrit.cloudera.org:8080/11406 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I79ec3a5ed974709e5e47be6b074d39ee89461f7f Gerrit-Change-Number: 11406 Gerrit-PatchSet: 2 Gerrit-Owner: Jim Apple <[email protected]> Gerrit-Reviewer: Dan Hecht <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Jim Apple <[email protected]> Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-Comment-Date: Sun, 16 Sep 2018 23:16:59 +0000 Gerrit-HasComments: Yes
