Tim Armstrong has posted comments on this change. Change subject: IMPALA-3376: Extra definition level when writing Parquet files ......................................................................
Patch Set 3: (1 comment) http://gerrit.cloudera.org:8080/#/c/3556/2/be/src/util/parquet-reader.cc File be/src/util/parquet-reader.cc: Line 149: void CheckDataPage(const ColumnChunk& col, const PageHeader& header, uint8_t* data) { > This looks odd to me, I think C++ requires constant array sizes for arrays Just saw this. Thought I'd comment since I have some additional info. The C++ standard doesn't allow variable-length arrays on the stack, but both gcc and clang support it. We use this in various places and compile with -Wno-vla to suppress warnings. Arguably we should avoid doing this, but it's useful to be able to allocate small amounts of working space without the overhead of malloc(). It's a bad idea though to allocate arrays on the stack if you don't have a fixed maximum size. E.g. if uncompressed_page_size is large, we could easily overflow the stack. -- To view, visit http://gerrit.cloudera.org:8080/3556 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: I2cafd7ef6b607ce6f815072b8af7395a892704d9 Gerrit-PatchSet: 3 Gerrit-Project: Impala Gerrit-Branch: cdh5-trunk Gerrit-Owner: Thomas Tauber-Marshall <[email protected]> Gerrit-Reviewer: Lars Volker <[email protected]> Gerrit-Reviewer: Matthew Jacobs <[email protected]> Gerrit-Reviewer: Thomas Tauber-Marshall <[email protected]> Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-HasComments: Yes
