Fix GitHub issue #3716: gcc-8 warnings

Summary:
Fix the following gcc-8 warnings:
- conflicting C language linkage declaration [-Werror]
- writing to an object with no trivial copy-assignment [-Werror=class-memaccess]
- array subscript -1 is below array bounds [-Werror=array-bounds]

Solves https://github.com/facebook/rocksdb/issues/3716
Closes https://github.com/facebook/rocksdb/pull/3736

Differential Revision: D7684161

Pulled By: yiwu-arbug

fbshipit-source-id: 47c0423d26b74add251f1d3595211eee1e41e54a

HISTORY.md

@@ -1,4 +1,12 @@
 # Rocksdb Change Log
+## 5.13.4 (6/12/2018)
+### Bug Fixes
+* Fix regression bug of Prev() with ReadOptions.iterate_upper_bound.
+
+## 5.13.3 (6/6/2018)
+### Bug Fixes
+* Fix assertion when reading bloom filter of SST files containing range deletions but no data
+
 ## 5.13.2 (5/25/2018)
 ### Public API Change
 * Introduced `CompressionOptions::kDefaultCompressionLevel`, which is a generic way to tell RocksDB to use the compression library's default level. It is now the default value for `CompressionOptions::level`. Previously the level defaulted to -1, which gave poor compression ratios in ZSTD.

build_tools/build_detect_platform

@@ -53,11 +53,13 @@ if [ -z "$ROCKSDB_NO_FBCODE" -a -d /mnt/gvfs/third-party ]; then
     FBCODE_BUILD="true"
     # If we're compiling with TSAN we need pic build
     PIC_BUILD=$COMPILE_WITH_TSAN
-    if [ -z "$ROCKSDB_FBCODE_BUILD_WITH_481" ]; then
-      source "$PWD/build_tools/fbcode_config.sh"
-    else
+    if [ -n "$ROCKSDB_FBCODE_BUILD_WITH_481" ]; then
       # we need this to build with MySQL. Don't use for other purposes.
       source "$PWD/build_tools/fbcode_config4.8.1.sh"
+    elif [ -n "$ROCKSDB_FBCODE_BUILD_WITH_5xx" ]; then
+      source "$PWD/build_tools/fbcode_config.sh"
+    else
+      source "$PWD/build_tools/fbcode_config_platform007.sh"
     fi
 fi
 

build_tools/dependencies_platform007.sh

@@ -0,0 +1,18 @@
+GCC_BASE=/mnt/gvfs/third-party2/gcc/6e8e715624fd15256a7970073387793dfcf79b46/7.x/centos7-native/b2ef2b6
+CLANG_BASE=/mnt/gvfs/third-party2/llvm-fb/ef37e1faa1c29782abfac1ae65a291b9b7966f6d/stable/centos7-native/c9f9104
+LIBGCC_BASE=/mnt/gvfs/third-party2/libgcc/c67031f0f739ac61575a061518d6ef5038f99f90/7.x/platform007/5620abc
+GLIBC_BASE=/mnt/gvfs/third-party2/glibc/60d6f124a78798b73944f5ba87c2306ae3460153/2.26/platform007/f259413
+SNAPPY_BASE=/mnt/gvfs/third-party2/snappy/7f9bdaada18f59bc27ec2b0871eb8a6144343aef/1.1.3/platform007/ca4da3d
+ZLIB_BASE=/mnt/gvfs/third-party2/zlib/22c2d65676fb7c23cfa797c4f6937f38b026f3cf/1.2.8/platform007/ca4da3d
+BZIP2_BASE=/mnt/gvfs/third-party2/bzip2/dc49a21c5fceec6456a7a28a94dcd16690af1337/1.0.6/platform007/ca4da3d
+LZ4_BASE=/mnt/gvfs/third-party2/lz4/907b498203d297947f3bb70b9466f47e100f1873/r131/platform007/ca4da3d
+ZSTD_BASE=/mnt/gvfs/third-party2/zstd/3ee276cbacfad3074e3f07bf826ac47f06970f4e/1.3.5/platform007/15a3614
+GFLAGS_BASE=/mnt/gvfs/third-party2/gflags/0b9929d2588991c65a57168bf88aff2db87c5d48/2.2.0/platform007/ca4da3d
+JEMALLOC_BASE=/mnt/gvfs/third-party2/jemalloc/9c910d36d6235cc40e8ff559358f1833452300ca/master/platform007/5b0f53e
+NUMA_BASE=/mnt/gvfs/third-party2/numa/9cbf2460284c669ed19c3ccb200a71f7dd7e53c7/2.0.11/platform007/ca4da3d
+LIBUNWIND_BASE=/mnt/gvfs/third-party2/libunwind/bf3d7497fe4e6d007354f0adffa16ce3003f8338/1.3/platform007/6f3e0a9
+TBB_BASE=/mnt/gvfs/third-party2/tbb/ff4e0b093534704d8abab678a4fd7f5ea7b094c7/2018_U5/platform007/ca4da3d
+KERNEL_HEADERS_BASE=/mnt/gvfs/third-party2/kernel-headers/b5c4a61a5c483ba24722005ae07895971a2ac707/fb/platform007/da39a3e
+BINUTILS_BASE=/mnt/gvfs/third-party2/binutils/92ff90349e2f43ea0a8246d8b1cf17b6869013e3/2.29.1/centos7-native/da39a3e
+VALGRIND_BASE=/mnt/gvfs/third-party2/valgrind/f3f697a28122e6bcd513273dd9c1ff23852fc59f/3.13.0/platform007/ca4da3d
+LUA_BASE=/mnt/gvfs/third-party2/lua/f0cd714433206d5139df61659eb7b28b1dea6683/5.3.4/platform007/5007832

build_tools/fbcode_config_platform007.sh

@@ -0,0 +1,157 @@
+#!/bin/sh
+#
+# Set environment variables so that we can compile rocksdb using
+# fbcode settings.  It uses the latest g++ and clang compilers and also
+# uses jemalloc
+# Environment variables that change the behavior of this script:
+# PIC_BUILD -- if true, it will only take pic versions of libraries from fbcode. libraries that don't have pic variant will not be included
+
+
+BASEDIR=`dirname $BASH_SOURCE`
+source "$BASEDIR/dependencies_platform007.sh"
+
+CFLAGS=""
+
+# libgcc
+LIBGCC_INCLUDE="$LIBGCC_BASE/include/c++/7.3.0"
+LIBGCC_LIBS=" -L $LIBGCC_BASE/lib"
+
+# glibc
+GLIBC_INCLUDE="$GLIBC_BASE/include"
+GLIBC_LIBS=" -L $GLIBC_BASE/lib"
+
+# snappy
+SNAPPY_INCLUDE=" -I $SNAPPY_BASE/include/"
+if test -z $PIC_BUILD; then
+  SNAPPY_LIBS=" $SNAPPY_BASE/lib/libsnappy.a"
+else
+  SNAPPY_LIBS=" $SNAPPY_BASE/lib/libsnappy_pic.a"
+fi
+CFLAGS+=" -DSNAPPY"
+
+if test -z $PIC_BUILD; then
+  # location of zlib headers and libraries
+  ZLIB_INCLUDE=" -I $ZLIB_BASE/include/"
+  ZLIB_LIBS=" $ZLIB_BASE/lib/libz.a"
+  CFLAGS+=" -DZLIB"
+
+  # location of bzip headers and libraries
+  BZIP_INCLUDE=" -I $BZIP2_BASE/include/"
+  BZIP_LIBS=" $BZIP2_BASE/lib/libbz2.a"
+  CFLAGS+=" -DBZIP2"
+
+  LZ4_INCLUDE=" -I $LZ4_BASE/include/"
+  LZ4_LIBS=" $LZ4_BASE/lib/liblz4.a"
+  CFLAGS+=" -DLZ4"
+fi
+
+ZSTD_INCLUDE=" -I $ZSTD_BASE/include/"
+if test -z $PIC_BUILD; then
+  ZSTD_LIBS=" $ZSTD_BASE/lib/libzstd.a"
+else
+  ZSTD_LIBS=" $ZSTD_BASE/lib/libzstd_pic.a"
+fi
+CFLAGS+=" -DZSTD"
+
+# location of gflags headers and libraries
+GFLAGS_INCLUDE=" -I $GFLAGS_BASE/include/"
+if test -z $PIC_BUILD; then
+  GFLAGS_LIBS=" $GFLAGS_BASE/lib/libgflags.a"
+else
+  GFLAGS_LIBS=" $GFLAGS_BASE/lib/libgflags_pic.a"
+fi
+CFLAGS+=" -DGFLAGS=gflags"
+
+# location of jemalloc
+JEMALLOC_INCLUDE=" -I $JEMALLOC_BASE/include/"
+JEMALLOC_LIB=" $JEMALLOC_BASE/lib/libjemalloc.a"
+
+if test -z $PIC_BUILD; then
+  # location of numa
+  NUMA_INCLUDE=" -I $NUMA_BASE/include/"
+  NUMA_LIB=" $NUMA_BASE/lib/libnuma.a"
+  CFLAGS+=" -DNUMA"
+
+  # location of libunwind
+  LIBUNWIND="$LIBUNWIND_BASE/lib/libunwind.a"
+fi
+
+# location of TBB
+TBB_INCLUDE=" -isystem $TBB_BASE/include/"
+if test -z $PIC_BUILD; then
+  TBB_LIBS="$TBB_BASE/lib/libtbb.a"
+else
+  TBB_LIBS="$TBB_BASE/lib/libtbb_pic.a"
+fi
+CFLAGS+=" -DTBB"
+
+# use Intel SSE support for checksum calculations
+export USE_SSE=1
+export PORTABLE=1
+
+BINUTILS="$BINUTILS_BASE/bin"
+AR="$BINUTILS/ar"
+
+DEPS_INCLUDE="$SNAPPY_INCLUDE $ZLIB_INCLUDE $BZIP_INCLUDE $LZ4_INCLUDE $ZSTD_INCLUDE $GFLAGS_INCLUDE $NUMA_INCLUDE $TBB_INCLUDE"
+
+STDLIBS="-L $GCC_BASE/lib64"
+
+CLANG_BIN="$CLANG_BASE/bin"
+CLANG_LIB="$CLANG_BASE/lib"
+CLANG_SRC="$CLANG_BASE/../../src"
+
+CLANG_ANALYZER="$CLANG_BIN/clang++"
+CLANG_SCAN_BUILD="$CLANG_SRC/llvm/tools/clang/tools/scan-build/bin/scan-build"
+
+if [ -z "$USE_CLANG" ]; then
+  # gcc
+  CC="$GCC_BASE/bin/gcc"
+  CXX="$GCC_BASE/bin/g++"
+
+  CFLAGS+=" -B$BINUTILS/gold"
+  CFLAGS+=" -isystem $LIBGCC_INCLUDE"
+  CFLAGS+=" -isystem $GLIBC_INCLUDE"
+  JEMALLOC=1
+else
+  # clang
+  CLANG_INCLUDE="$CLANG_LIB/clang/stable/include"
+  CC="$CLANG_BIN/clang"
+  CXX="$CLANG_BIN/clang++"
+
+  KERNEL_HEADERS_INCLUDE="$KERNEL_HEADERS_BASE/include"
+
+  CFLAGS+=" -B$BINUTILS/gold -nostdinc -nostdlib"
+  CFLAGS+=" -isystem $LIBGCC_BASE/include/c++/7.x "
+  CFLAGS+=" -isystem $LIBGCC_BASE/include/c++/7.x/x86_64-facebook-linux "
+  CFLAGS+=" -isystem $GLIBC_INCLUDE"
+  CFLAGS+=" -isystem $LIBGCC_INCLUDE"
+  CFLAGS+=" -isystem $CLANG_INCLUDE"
+  CFLAGS+=" -isystem $KERNEL_HEADERS_INCLUDE/linux "
+  CFLAGS+=" -isystem $KERNEL_HEADERS_INCLUDE "
+  CFLAGS+=" -Wno-expansion-to-defined "
+  CXXFLAGS="-nostdinc++"
+fi
+
+CFLAGS+=" $DEPS_INCLUDE"
+CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX -DROCKSDB_FALLOCATE_PRESENT -DROCKSDB_MALLOC_USABLE_SIZE -DROCKSDB_RANGESYNC_PRESENT -DROCKSDB_SCHED_GETCPU_PRESENT -DROCKSDB_SUPPORT_THREAD_LOCAL -DHAVE_SSE42"
+CXXFLAGS+=" $CFLAGS"
+
+EXEC_LDFLAGS=" $SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $NUMA_LIB $TBB_LIBS"
+EXEC_LDFLAGS+=" -B$BINUTILS/gold"
+EXEC_LDFLAGS+=" -Wl,--dynamic-linker,/usr/local/fbcode/platform007/lib/ld.so"
+EXEC_LDFLAGS+=" $LIBUNWIND"
+EXEC_LDFLAGS+=" -Wl,-rpath=/usr/local/fbcode/platform007/lib"
+# required by libtbb
+EXEC_LDFLAGS+=" -ldl"
+
+PLATFORM_LDFLAGS="$LIBGCC_LIBS $GLIBC_LIBS $STDLIBS -lgcc -lstdc++"
+
+EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $TBB_LIBS"
+
+VALGRIND_VER="$VALGRIND_BASE/bin/"
+
+# lua not supported because it's on track for deprecation, I think
+LUA_PATH=
+LUA_LIB=
+
+export CC CXX AR CFLAGS CXXFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED VALGRIND_VER JEMALLOC_LIB JEMALLOC_INCLUDE CLANG_ANALYZER CLANG_SCAN_BUILD LUA_PATH LUA_LIB

build_tools/rocksdb-lego-determinator

@@ -85,8 +85,9 @@ NON_SHM="TMPD=/tmp/rocksdb_test_tmp"
 GCC_481="ROCKSDB_FBCODE_BUILD_WITH_481=1"
 ASAN="COMPILE_WITH_ASAN=1"
 CLANG="USE_CLANG=1"
-LITE="OPT=\"-DROCKSDB_LITE -g\""
-TSAN="COMPILE_WITH_TSAN=1"
+# in gcc-5 there are known problems with TSAN like https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71090.
+# using platform007 gives us gcc-8 or higher which has that bug fixed.
+TSAN="ROCKSDB_FBCODE_BUILD_WITH_PLATFORM007=1 COMPILE_WITH_TSAN=1"
 UBSAN="COMPILE_WITH_UBSAN=1"
 DISABLE_JEMALLOC="DISABLE_JEMALLOC=1"
 HTTP_PROXY="https_proxy=http://fwdproxy.29.prn1:8080 http_proxy=http://fwdproxy.29.prn1:8080 ftp_proxy=http://fwdproxy.29.prn1:8080"

build_tools/update_dependencies.sh

@@ -53,6 +53,45 @@ function get_lib_base()
   log_variable $__res_var
 }
 
+###########################################################
+#                platform007 dependencies                 #
+###########################################################
+
+OUTPUT="$BASEDIR/dependencies_platform007.sh"
+
+rm -f "$OUTPUT"
+touch "$OUTPUT"
+
+echo "Writing dependencies to $OUTPUT"
+
+# Compilers locations
+GCC_BASE=`readlink -f $TP2_LATEST/gcc/7.x/centos7-native/*/`
+CLANG_BASE=`readlink -f $TP2_LATEST/llvm-fb/stable/centos7-native/*/`
+
+log_variable GCC_BASE
+log_variable CLANG_BASE
+
+# Libraries locations
+get_lib_base libgcc     7.x     platform007
+get_lib_base glibc      2.26    platform007
+get_lib_base snappy     LATEST  platform007
+get_lib_base zlib       LATEST  platform007
+get_lib_base bzip2      LATEST  platform007
+get_lib_base lz4        LATEST  platform007
+get_lib_base zstd       LATEST  platform007
+get_lib_base gflags     LATEST  platform007
+get_lib_base jemalloc   LATEST  platform007
+get_lib_base numa       LATEST  platform007
+get_lib_base libunwind  LATEST  platform007
+get_lib_base tbb        LATEST  platform007
+
+get_lib_base kernel-headers fb platform007
+get_lib_base binutils   LATEST centos7-native
+get_lib_base valgrind   LATEST platform007
+get_lib_base lua        5.3.4  platform007
+
+git diff $OUTPUT
+
 ###########################################################
 #                   5.x dependencies                      #
 ###########################################################

db/c.cc

@@ -1403,23 +1403,24 @@ void rocksdb_writebatch_put_log_data(
   b->rep.PutLogData(Slice(blob, len));
 }
 
+class H : public WriteBatch::Handler {
+ public:
+  void* state_;
+  void (*put_)(void*, const char* k, size_t klen, const char* v, size_t vlen);
+  void (*deleted_)(void*, const char* k, size_t klen);
+  virtual void Put(const Slice& key, const Slice& value) override {
+    (*put_)(state_, key.data(), key.size(), value.data(), value.size());
+  }
+  virtual void Delete(const Slice& key) override {
+    (*deleted_)(state_, key.data(), key.size());
+  }
+};
+
 void rocksdb_writebatch_iterate(
     rocksdb_writebatch_t* b,
     void* state,
     void (*put)(void*, const char* k, size_t klen, const char* v, size_t vlen),
     void (*deleted)(void*, const char* k, size_t klen)) {
-  class H : public WriteBatch::Handler {
-   public:
-    void* state_;
-    void (*put_)(void*, const char* k, size_t klen, const char* v, size_t vlen);
-    void (*deleted_)(void*, const char* k, size_t klen);
-    virtual void Put(const Slice& key, const Slice& value) override {
-      (*put_)(state_, key.data(), key.size(), value.data(), value.size());
-    }
-    virtual void Delete(const Slice& key) override {
-      (*deleted_)(state_, key.data(), key.size());
-    }
-  };
   H handler;
   handler.state_ = state;
   handler.put_ = put;
@@ -1664,18 +1665,6 @@ void rocksdb_writebatch_wi_iterate(
     void* state,
     void (*put)(void*, const char* k, size_t klen, const char* v, size_t vlen),
     void (*deleted)(void*, const char* k, size_t klen)) {
-  class H : public WriteBatch::Handler {
-   public:
-    void* state_;
-    void (*put_)(void*, const char* k, size_t klen, const char* v, size_t vlen);
-    void (*deleted_)(void*, const char* k, size_t klen);
-    virtual void Put(const Slice& key, const Slice& value) override {
-      (*put_)(state_, key.data(), key.size(), value.data(), value.size());
-    }
-    virtual void Delete(const Slice& key) override {
-      (*deleted_)(state_, key.data(), key.size());
-    }
-  };
   H handler;
   handler.state_ = state;
   handler.put_ = put;
@@ -3124,20 +3113,21 @@ void rocksdb_slicetransform_destroy(rocksdb_slicetransform_t* st) {
   delete st;
 }
 
+struct Wrapper : public rocksdb_slicetransform_t {
+  const SliceTransform* rep_;
+  ~Wrapper() { delete rep_; }
+  const char* Name() const override { return rep_->Name(); }
+  Slice Transform(const Slice& src) const override {
+    return rep_->Transform(src);
+  }
+  bool InDomain(const Slice& src) const override {
+    return rep_->InDomain(src);
+  }
+  bool InRange(const Slice& src) const override { return rep_->InRange(src); }
+  static void DoNothing(void*) { }
+};
+
 rocksdb_slicetransform_t* rocksdb_slicetransform_create_fixed_prefix(size_t prefixLen) {
-  struct Wrapper : public rocksdb_slicetransform_t {
-    const SliceTransform* rep_;
-    ~Wrapper() { delete rep_; }
-    const char* Name() const override { return rep_->Name(); }
-    Slice Transform(const Slice& src) const override {
-      return rep_->Transform(src);
-    }
-    bool InDomain(const Slice& src) const override {
-      return rep_->InDomain(src);
-    }
-    bool InRange(const Slice& src) const override { return rep_->InRange(src); }
-    static void DoNothing(void*) { }
-  };
   Wrapper* wrapper = new Wrapper;
   wrapper->rep_ = rocksdb::NewFixedPrefixTransform(prefixLen);
   wrapper->state_ = nullptr;
@@ -3146,19 +3136,6 @@ rocksdb_slicetransform_t* rocksdb_slicetransform_create_fixed_prefix(size_t pref
 }
 
 rocksdb_slicetransform_t* rocksdb_slicetransform_create_noop() {
-  struct Wrapper : public rocksdb_slicetransform_t {
-    const SliceTransform* rep_;
-    ~Wrapper() { delete rep_; }
-    const char* Name() const override { return rep_->Name(); }
-    Slice Transform(const Slice& src) const override {
-      return rep_->Transform(src);
-    }
-    bool InDomain(const Slice& src) const override {
-      return rep_->InDomain(src);
-    }
-    bool InRange(const Slice& src) const override { return rep_->InRange(src); }
-    static void DoNothing(void*) { }
-  };
   Wrapper* wrapper = new Wrapper;
   wrapper->rep_ = rocksdb::NewNoopTransform();
   wrapper->state_ = nullptr;

db/db_iter_test.cc

@@ -36,7 +36,9 @@ class TestIterator : public InternalIterator {
         valid_(false),
         sequence_number_(0),
         iter_(0),
-        cmp(comparator) {}
+        cmp(comparator) {
+    data_.reserve(16);
+  }
 
   void AddPut(std::string argkey, std::string argvalue) {
     Add(argkey, kTypeValue, argvalue);
@@ -2549,7 +2551,7 @@ TEST_F(DBIterWithMergeIterTest, InnerMergeIteratorDataRace1) {
   // MergeIterator::Prev() realized the mem table iterator is at its end
   // and before an SeekToLast() is called.
   rocksdb::SyncPoint::GetInstance()->SetCallBack(
-      "MergeIterator::Prev:BeforeSeekToLast",
+      "MergeIterator::Prev:BeforePrev",
       [&](void* arg) { internal_iter2_->Add("z", kTypeValue, "7", 12u); });
   rocksdb::SyncPoint::GetInstance()->EnableProcessing();
 
@@ -2585,7 +2587,7 @@ TEST_F(DBIterWithMergeIterTest, InnerMergeIteratorDataRace2) {
   // mem table after MergeIterator::Prev() realized the mem tableiterator is at
   // its end and before an SeekToLast() is called.
   rocksdb::SyncPoint::GetInstance()->SetCallBack(
-      "MergeIterator::Prev:BeforeSeekToLast", [&](void* arg) {
+      "MergeIterator::Prev:BeforePrev", [&](void* arg) {
         internal_iter2_->Add("z", kTypeValue, "7", 12u);
         internal_iter2_->Add("z", kTypeValue, "7", 11u);
       });
@@ -2623,7 +2625,7 @@ TEST_F(DBIterWithMergeIterTest, InnerMergeIteratorDataRace3) {
   // mem table after MergeIterator::Prev() realized the mem table iterator is at
   // its end and before an SeekToLast() is called.
   rocksdb::SyncPoint::GetInstance()->SetCallBack(
-      "MergeIterator::Prev:BeforeSeekToLast", [&](void* arg) {
+      "MergeIterator::Prev:BeforePrev", [&](void* arg) {
         internal_iter2_->Add("z", kTypeValue, "7", 16u, true);
         internal_iter2_->Add("z", kTypeValue, "7", 15u, true);
         internal_iter2_->Add("z", kTypeValue, "7", 14u, true);

db/db_iterator_test.cc

@@ -2043,6 +2043,43 @@ TEST_P(DBIteratorTest, CreationFailure) {
   delete iter;
 }
 
+TEST_P(DBIteratorTest, UpperBoundWithChangeDirection) {
+  Options options = CurrentOptions();
+  options.max_sequential_skip_in_iterations = 3;
+  DestroyAndReopen(options);
+
+  // write a bunch of kvs to the database.
+  ASSERT_OK(Put("a", "1"));
+  ASSERT_OK(Put("y", "1"));
+  ASSERT_OK(Put("y1", "1"));
+  ASSERT_OK(Put("y2", "1"));
+  ASSERT_OK(Put("y3", "1"));
+  ASSERT_OK(Put("z", "1"));
+  ASSERT_OK(Flush());
+  ASSERT_OK(Put("a", "1"));
+  ASSERT_OK(Put("z", "1"));
+  ASSERT_OK(Put("bar", "1"));
+  ASSERT_OK(Put("foo", "1"));
+
+  std::string upper_bound = "x";
+  Slice ub_slice(upper_bound);
+  ReadOptions ro;
+  ro.iterate_upper_bound = &ub_slice;
+  ro.max_skippable_internal_keys = 1000;
+
+  Iterator* iter = NewIterator(ro);
+  iter->Seek("foo");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("foo", iter->key().ToString());
+
+  iter->Prev();
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_OK(iter->status());
+  ASSERT_EQ("bar", iter->key().ToString());
+
+  delete iter;
+}
+
 TEST_P(DBIteratorTest, TableFilter) {
   ASSERT_OK(Put("a", "1"));
   dbfull()->Flush(FlushOptions());
@@ -2109,6 +2146,47 @@ TEST_P(DBIteratorTest, TableFilter) {
   }
 }
 
+TEST_P(DBIteratorTest, UpperBoundWithPrevReseek) {
+  Options options = CurrentOptions();
+  options.max_sequential_skip_in_iterations = 3;
+  DestroyAndReopen(options);
+
+  // write a bunch of kvs to the database.
+  ASSERT_OK(Put("a", "1"));
+  ASSERT_OK(Put("y", "1"));
+  ASSERT_OK(Put("z", "1"));
+  ASSERT_OK(Flush());
+  ASSERT_OK(Put("a", "1"));
+  ASSERT_OK(Put("z", "1"));
+  ASSERT_OK(Put("bar", "1"));
+  ASSERT_OK(Put("foo", "1"));
+  ASSERT_OK(Put("foo", "2"));
+
+  ASSERT_OK(Put("foo", "3"));
+  ASSERT_OK(Put("foo", "4"));
+  ASSERT_OK(Put("foo", "5"));
+  const Snapshot* snapshot = db_->GetSnapshot();
+  ASSERT_OK(Put("foo", "6"));
+
+  std::string upper_bound = "x";
+  Slice ub_slice(upper_bound);
+  ReadOptions ro;
+  ro.snapshot = snapshot;
+  ro.iterate_upper_bound = &ub_slice;
+
+  Iterator* iter = NewIterator(ro);
+  iter->SeekForPrev("goo");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("foo", iter->key().ToString());
+  iter->Prev();
+
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("bar", iter->key().ToString());
+
+  delete iter;
+  db_->ReleaseSnapshot(snapshot);
+}
+
 TEST_P(DBIteratorTest, SkipStatistics) {
   Options options = CurrentOptions();
   options.statistics = rocksdb::CreateDBStatistics();

include/rocksdb/version.h

@@ -6,7 +6,7 @@
 
 #define ROCKSDB_MAJOR 5
 #define ROCKSDB_MINOR 13
-#define ROCKSDB_PATCH 2
+#define ROCKSDB_PATCH 4
 
 // Do not use these. We made the mistake of declaring macros starting with
 // double underscore. Now we have to live with our choice. We'll deprecate these

memtable/inlineskiplist.h

@@ -280,7 +280,7 @@ struct InlineSkipList<Comparator>::Node {
   // next_[0].  This is used for passing data from AllocateKey to Insert.
   void StashHeight(const int height) {
     assert(sizeof(int) <= sizeof(next_[0]));
-    memcpy(&next_[0], &height, sizeof(int));
+    memcpy(static_cast<void*>(&next_[0]), &height, sizeof(int));
   }
 
   // Retrieves the value passed to StashHeight.  Undefined after a call
@@ -300,30 +300,30 @@ struct InlineSkipList<Comparator>::Node {
     assert(n >= 0);
     // Use an 'acquire load' so that we observe a fully initialized
     // version of the returned Node.
-    return (next_[-n].load(std::memory_order_acquire));
+    return ((&next_[0] - n)->load(std::memory_order_acquire));
   }
 
   void SetNext(int n, Node* x) {
     assert(n >= 0);
     // Use a 'release store' so that anybody who reads through this
     // pointer observes a fully initialized version of the inserted node.
-    next_[-n].store(x, std::memory_order_release);
+    (&next_[0] - n)->store(x, std::memory_order_release);
   }
 
   bool CASNext(int n, Node* expected, Node* x) {
     assert(n >= 0);
-    return next_[-n].compare_exchange_strong(expected, x);
+    return (&next_[0] - n)->compare_exchange_strong(expected, x);
   }
 
   // No-barrier variants that can be safely used in a few locations.
   Node* NoBarrier_Next(int n) {
     assert(n >= 0);
-    return next_[-n].load(std::memory_order_relaxed);
+    return (&next_[0] - n)->load(std::memory_order_relaxed);
   }
 
   void NoBarrier_SetNext(int n, Node* x) {
     assert(n >= 0);
-    next_[-n].store(x, std::memory_order_relaxed);
+    (&next_[0] - n)->store(x, std::memory_order_relaxed);
   }
 
   // Insert node after prev on specific level.

table/block_based_filter_block.cc

@@ -67,7 +67,8 @@ BlockBasedFilterBlockBuilder::BlockBasedFilterBlockBuilder(
       prefix_extractor_(prefix_extractor),
       whole_key_filtering_(table_opt.whole_key_filtering),
       prev_prefix_start_(0),
-      prev_prefix_size_(0) {
+      prev_prefix_size_(0),
+      num_added_(0) {
   assert(policy_);
 }
 
@@ -91,6 +92,7 @@ void BlockBasedFilterBlockBuilder::Add(const Slice& key) {
 
 // Add key to filter if needed
 inline void BlockBasedFilterBlockBuilder::AddKey(const Slice& key) {
+  num_added_++;
   start_.push_back(entries_.size());
   entries_.append(key.data(), key.size());
 }
@@ -106,10 +108,9 @@ inline void BlockBasedFilterBlockBuilder::AddPrefix(const Slice& key) {
   Slice prefix = prefix_extractor_->Transform(key);
   // insert prefix only when it's different from the previous prefix.
   if (prev.size() == 0 || prefix != prev) {
-    start_.push_back(entries_.size());
+    AddKey(prefix);
     prev_prefix_start_ = entries_.size();
     prev_prefix_size_ = prefix.size();
-    entries_.append(prefix.data(), prefix.size());
   }
 }
 

table/block_based_filter_block.h

@@ -41,6 +41,7 @@ class BlockBasedFilterBlockBuilder : public FilterBlockBuilder {
   virtual bool IsBlockBased() override { return true; }
   virtual void StartBlock(uint64_t block_offset) override;
   virtual void Add(const Slice& key) override;
+  virtual size_t NumAdded() const override { return num_added_; }
   virtual Slice Finish(const BlockHandle& tmp, Status* status) override;
   using FilterBlockBuilder::Finish;
 
@@ -65,6 +66,7 @@ class BlockBasedFilterBlockBuilder : public FilterBlockBuilder {
   std::string result_;              // Filter data computed so far
   std::vector<Slice> tmp_entries_;  // policy_->CreateFilter() argument
   std::vector<uint32_t> filter_offsets_;
+  size_t num_added_;                // Number of keys added
 
   // No copying allowed
   BlockBasedFilterBlockBuilder(const BlockBasedFilterBlockBuilder&);

table/block_based_filter_block_test.cc

@@ -65,6 +65,7 @@ TEST_F(FilterBlockTest, EmptyBuilder) {
 
 TEST_F(FilterBlockTest, SingleChunk) {
   BlockBasedFilterBlockBuilder builder(nullptr, table_options_);
+  ASSERT_EQ(0, builder.NumAdded());
   builder.StartBlock(100);
   builder.Add("foo");
   builder.Add("bar");
@@ -73,6 +74,7 @@ TEST_F(FilterBlockTest, SingleChunk) {
   builder.Add("box");
   builder.StartBlock(300);
   builder.Add("hello");
+  ASSERT_EQ(5, builder.NumAdded());
   BlockContents block(builder.Finish(), false, kNoCompression);
   BlockBasedFilterBlockReader reader(nullptr, table_options_, true,
                                      std::move(block), nullptr);

table/block_based_table_builder.cc

@@ -650,8 +650,11 @@ Status BlockBasedTableBuilder::Finish() {
 
   BlockHandle filter_block_handle, metaindex_block_handle, index_block_handle,
       compression_dict_block_handle, range_del_block_handle;
+
   // Write filter block
-  if (ok() && r->filter_builder != nullptr) {
+  bool empty_filter_block = (r->filter_builder == nullptr ||
+                             r->filter_builder->NumAdded() == 0);
+  if (ok() && !empty_filter_block) {
     Status s = Status::Incomplete();
     while (s.IsIncomplete()) {
       Slice filter_content = r->filter_builder->Finish(filter_block_handle, &s);
@@ -687,7 +690,7 @@ Status BlockBasedTableBuilder::Finish() {
   }
 
   if (ok()) {
-    if (r->filter_builder != nullptr) {
+    if (!empty_filter_block) {
       // Add mapping from "<filter_block_prefix>.Name" to location
       // of filter data.
       std::string key;

table/filter_block.h

@@ -51,6 +51,7 @@ class FilterBlockBuilder {
   virtual bool IsBlockBased() = 0;                    // If is blockbased filter
   virtual void StartBlock(uint64_t block_offset) = 0;  // Start new block filter
   virtual void Add(const Slice& key) = 0;      // Add a key to current filter
+  virtual size_t NumAdded() const = 0;         // Number of keys added
   Slice Finish() {                             // Generate Filter
     const BlockHandle empty_handle;
     Status dont_care_status;

table/full_filter_block.h

@@ -45,6 +45,7 @@ class FullFilterBlockBuilder : public FilterBlockBuilder {
   virtual bool IsBlockBased() override { return false; }
   virtual void StartBlock(uint64_t /*block_offset*/) override {}
   virtual void Add(const Slice& key) override;
+  virtual size_t NumAdded() const override { return num_added_; }
   virtual Slice Finish(const BlockHandle& tmp, Status* status) override;
   using FilterBlockBuilder::Finish;
 

table/full_filter_block_test.cc

@@ -163,11 +163,13 @@ TEST_F(FullFilterBlockTest, EmptyBuilder) {
 TEST_F(FullFilterBlockTest, SingleChunk) {
   FullFilterBlockBuilder builder(
       nullptr, true, table_options_.filter_policy->GetFilterBitsBuilder());
+  ASSERT_EQ(0, builder.NumAdded());
   builder.Add("foo");
   builder.Add("bar");
   builder.Add("box");
   builder.Add("box");
   builder.Add("hello");
+  ASSERT_EQ(5, builder.NumAdded());
   Slice block = builder.Finish();
   FullFilterBlockReader reader(
       nullptr, true, block,

table/merging_iterator.cc

@@ -193,23 +193,11 @@ class MergingIterator : public InternalIterator {
       InitMaxHeap();
       for (auto& child : children_) {
         if (&child != current_) {
-          if (!prefix_seek_mode_) {
-            child.Seek(key());
-            if (child.Valid()) {
-              // Child is at first entry >= key().  Step back one to be < key()
-              TEST_SYNC_POINT_CALLBACK("MergeIterator::Prev:BeforePrev",
-                                       &child);
-              child.Prev();
-            } else {
-              // Child has no entries >= key().  Position at last entry.
-              TEST_SYNC_POINT("MergeIterator::Prev:BeforeSeekToLast");
-              child.SeekToLast();
-            }
-          } else {
-            child.SeekForPrev(key());
-            if (child.Valid() && comparator_->Equal(key(), child.key())) {
-              child.Prev();
-            }
+          child.SeekForPrev(key());
+          // Child is at first entry >= key().  Step back one to be < key()
+          TEST_SYNC_POINT_CALLBACK("MergeIterator::Prev:BeforePrev", &child);
+          if (child.Valid() && comparator_->Equal(key(), child.key())) {
+            child.Prev();
           }
         }
         if (child.Valid()) {

table/partitioned_filter_block.cc

@@ -25,7 +25,8 @@ PartitionedFilterBlockBuilder::PartitionedFilterBlockBuilder(
                              filter_bits_builder),
       index_on_filter_block_builder_(index_block_restart_interval),
       p_index_builder_(p_index_builder),
-      filters_in_partition_(0) {
+      filters_in_partition_(0),
+      num_added_(0) {
   filters_per_partition_ =
       filter_bits_builder_->CalculateNumEntry(partition_size);
 }
@@ -53,6 +54,7 @@ void PartitionedFilterBlockBuilder::AddKey(const Slice& key) {
   MaybeCutAFilterBlock();
   filter_bits_builder_->AddKey(key);
   filters_in_partition_++;
+  num_added_++;
 }
 
 Slice PartitionedFilterBlockBuilder::Finish(

table/partitioned_filter_block.h

@@ -33,6 +33,8 @@ class PartitionedFilterBlockBuilder : public FullFilterBlockBuilder {
 
   void AddKey(const Slice& key) override;
 
+  size_t NumAdded() const override { return num_added_; }
+
   virtual Slice Finish(const BlockHandle& last_partition_block_handle,
                        Status* status) override;
 
@@ -59,6 +61,8 @@ class PartitionedFilterBlockBuilder : public FullFilterBlockBuilder {
   uint32_t filters_per_partition_;
   // The current number of filters in the last partition
   uint32_t filters_in_partition_;
+  // Number of keys added
+  size_t num_added_;
 };
 
 class PartitionedFilterBlockReader : public FilterBlockReader,