Trimmed vtables of trailing zeroes.

This is something the format supports, but none of the builders
were doing. Can save 10-20% on FlatBuffer binary size!

Also fixed the Go tests.

Change-Id: I616c56ce9bbcfcaee23aa24f0532fcb60b6a8c75
Tested: on Linux.

go/builder.go

@@ -110,6 +110,11 @@ func (b *Builder) WriteVtable() (n UOffsetT) {
 	objectOffset := b.Offset()
 	existingVtable := UOffsetT(0)
 
+	// Trim vtable of trailing zeroes.
+	i := len(b.vtable) - 1;
+	for ; i >= 0 && b.vtable[i] == 0; i-- {}
+	b.vtable = b.vtable[:i + 1];
+
 	// Search backwards through existing vtables, because similar vtables
 	// are likely to have been recently appended. See
 	// BenchmarkVtableDeduplication for a case in which this heuristic

include/flatbuffers/flatbuffers.h

@@ -704,8 +704,8 @@ class FlatBufferBuilder
   explicit FlatBufferBuilder(size_t initial_size = 1024,
                              Allocator *allocator = nullptr,
                              bool own_allocator = false)
-    : buf_(initial_size, allocator, own_allocator), nested(false),
-      finished(false), minalign_(1), force_defaults_(false),
+    : buf_(initial_size, allocator, own_allocator), max_voffset_(0),
+      nested(false), finished(false), minalign_(1), force_defaults_(false),
       dedup_vtables_(true), string_pool(nullptr) {
     offsetbuf_.reserve(16);  // Avoid first few reallocs.
     vtables_.reserve(16);
@@ -725,7 +725,7 @@ class FlatBufferBuilder
   /// to construct another buffer.
   void Clear() {
     buf_.clear();
-    offsetbuf_.clear();
+    ClearOffsets();
     nested = false;
     finished = false;
     vtables_.clear();
@@ -839,6 +839,7 @@ class FlatBufferBuilder
   void TrackField(voffset_t field, uoffset_t off) {
     FieldLoc fl = { off, field };
     offsetbuf_.push_back(fl);
+    max_voffset_ = (std::max)(max_voffset_, field);
   }
 
   // Like PushElement, but additionally tracks the field this represents.
@@ -899,7 +900,7 @@ class FlatBufferBuilder
   // This finishes one serialized object by generating the vtable if it's a
   // table, comparing it against existing vtables, and writing the
   // resulting vtable offset.
-  uoffset_t EndTable(uoffset_t start, voffset_t numfields) {
+  uoffset_t EndTable(uoffset_t start) {
     // If you get this assert, a corresponding StartTable wasn't called.
     assert(nested);
     // Write the vtable offset, which is the start of any Table.
@@ -908,11 +909,17 @@ class FlatBufferBuilder
     // Write a vtable, which consists entirely of voffset_t elements.
     // It starts with the number of offsets, followed by a type id, followed
     // by the offsets themselves. In reverse:
-    buf_.fill_big(numfields * sizeof(voffset_t));
+    // Include space for the last offset and ensure empty tables have a
+    // minimum size.
+    max_voffset_ = (std::max)(static_cast<voffset_t>(max_voffset_ +
+                                                     sizeof(voffset_t)),
+                              FieldIndexToOffset(0));
+    buf_.fill_big(max_voffset_);
     auto table_object_size = vtableoffsetloc - start;
     assert(table_object_size < 0x10000);  // Vtable use 16bit offsets.
-    PushElement<voffset_t>(static_cast<voffset_t>(table_object_size));
-    PushElement<voffset_t>(FieldIndexToOffset(numfields));
+    WriteScalar<voffset_t>(buf_.data() + sizeof(voffset_t),
+                           static_cast<voffset_t>(table_object_size));
+    WriteScalar<voffset_t>(buf_.data(), max_voffset_);
     // Write the offsets into the table
     for (auto field_location = offsetbuf_.begin();
               field_location != offsetbuf_.end();
@@ -922,7 +929,7 @@ class FlatBufferBuilder
       assert(!ReadScalar<voffset_t>(buf_.data() + field_location->id));
       WriteScalar<voffset_t>(buf_.data() + field_location->id, pos);
     }
-    offsetbuf_.clear();
+    ClearOffsets();
     auto vt1 = reinterpret_cast<voffset_t *>(buf_.data());
     auto vt1_size = ReadScalar<voffset_t>(vt1);
     auto vt_use = GetSize();
@@ -955,6 +962,11 @@ class FlatBufferBuilder
     return vtableoffsetloc;
   }
 
+  // DEPRECATED: call the version above instead.
+  uoffset_t EndTable(uoffset_t start, voffset_t /*numfields*/) {
+    return EndTable(start);
+  }
+
   // This checks a required field has been set in a given table that has
   // just been constructed.
   template<typename T> void Required(Offset<T> table, voffset_t field) {
@@ -973,7 +985,10 @@ class FlatBufferBuilder
 
   uoffset_t EndStruct() { return GetSize(); }
 
-  void ClearOffsets() { offsetbuf_.clear(); }
+  void ClearOffsets() {
+    offsetbuf_.clear();
+    max_voffset_ = 0;
+  }
 
   // Aligns such that when "len" bytes are written, an object can be written
   // after it with "alignment" without padding.
@@ -1510,6 +1525,9 @@ class FlatBufferBuilder
 
   // Accumulating offsets of table members while it is being built.
   std::vector<FieldLoc> offsetbuf_;
+  // Track how much of the vtable is in use, so we can output the most compact
+  // possible vtable.
+  voffset_t max_voffset_;
 
   // Ensure objects are not nested.
   bool nested;

include/flatbuffers/reflection_generated.h

@@ -42,6 +42,29 @@ enum BaseType {
   Union = 16
 };
 
+inline BaseType (&EnumValuesBaseType())[17] {
+  static BaseType values[] = {
+    None,
+    UType,
+    Bool,
+    Byte,
+    UByte,
+    Short,
+    UShort,
+    Int,
+    UInt,
+    Long,
+    ULong,
+    Float,
+    Double,
+    String,
+    Vector,
+    Obj,
+    Union
+  };
+  return values;
+}
+
 inline const char **EnumNamesBaseType() {
   static const char *names[] = {
     "None",
@@ -113,7 +136,7 @@ struct TypeBuilder {
   }
   TypeBuilder &operator=(const TypeBuilder &);
   flatbuffers::Offset<Type> Finish() {
-    const auto end = fbb_.EndTable(start_, 3);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Type>(end);
     return o;
   }
@@ -173,7 +196,7 @@ struct KeyValueBuilder {
   }
   KeyValueBuilder &operator=(const KeyValueBuilder &);
   flatbuffers::Offset<KeyValue> Finish() {
-    const auto end = fbb_.EndTable(start_, 2);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<KeyValue>(end);
     fbb_.Required(o, KeyValue::VT_KEY);
     return o;
@@ -266,7 +289,7 @@ struct EnumValBuilder {
   }
   EnumValBuilder &operator=(const EnumValBuilder &);
   flatbuffers::Offset<EnumVal> Finish() {
-    const auto end = fbb_.EndTable(start_, 4);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<EnumVal>(end);
     fbb_.Required(o, EnumVal::VT_NAME);
     return o;
@@ -381,7 +404,7 @@ struct EnumBuilder {
   }
   EnumBuilder &operator=(const EnumBuilder &);
   flatbuffers::Offset<Enum> Finish() {
-    const auto end = fbb_.EndTable(start_, 6);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Enum>(end);
     fbb_.Required(o, Enum::VT_NAME);
     fbb_.Required(o, Enum::VT_VALUES);
@@ -544,7 +567,7 @@ struct FieldBuilder {
   }
   FieldBuilder &operator=(const FieldBuilder &);
   flatbuffers::Offset<Field> Finish() {
-    const auto end = fbb_.EndTable(start_, 11);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Field>(end);
     fbb_.Required(o, Field::VT_NAME);
     fbb_.Required(o, Field::VT_TYPE);
@@ -695,7 +718,7 @@ struct ObjectBuilder {
   }
   ObjectBuilder &operator=(const ObjectBuilder &);
   flatbuffers::Offset<Object> Finish() {
-    const auto end = fbb_.EndTable(start_, 7);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Object>(end);
     fbb_.Required(o, Object::VT_NAME);
     fbb_.Required(o, Object::VT_FIELDS);
@@ -808,7 +831,7 @@ struct SchemaBuilder {
   }
   SchemaBuilder &operator=(const SchemaBuilder &);
   flatbuffers::Offset<Schema> Finish() {
-    const auto end = fbb_.EndTable(start_, 5);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Schema>(end);
     fbb_.Required(o, Schema::VT_OBJECTS);
     fbb_.Required(o, Schema::VT_ENUMS);

java/com/google/flatbuffers/FlatBufferBuilder.java

@@ -478,7 +478,7 @@ public class FlatBufferBuilder {
         obj.sortTables(offsets, bb);
         return createVectorOfTables(offsets);
     }
-	
+
    /**
     * Encode the string `s` in the buffer using UTF-8.  If {@code s} is
     * already a {@link CharBuffer}, this method is allocation free.
@@ -744,7 +744,11 @@ public class FlatBufferBuilder {
         addInt(0);
         int vtableloc = offset();
         // Write out the current vtable.
-        for (int i = vtable_in_use - 1; i >= 0 ; i--) {
+        int i = vtable_in_use - 1;
+        // Trim trailing zeroes.
+        for (; i >= 0 && vtable[i] == 0; i--) {}
+        int trimmed_size = i + 1;
+        for (; i >= 0 ; i--) {
             // Offset relative to the start of the table.
             short off = (short)(vtable[i] != 0 ? vtableloc - vtable[i] : 0);
             addShort(off);
@@ -752,12 +756,12 @@ public class FlatBufferBuilder {
 
         final int standard_fields = 2; // The fields below:
         addShort((short)(vtableloc - object_start));
-        addShort((short)((vtable_in_use + standard_fields) * SIZEOF_SHORT));
+        addShort((short)((trimmed_size + standard_fields) * SIZEOF_SHORT));
 
         // Search for an existing vtable that matches the current one.
         int existing_vtable = 0;
         outer_loop:
-        for (int i = 0; i < num_vtables; i++) {
+        for (i = 0; i < num_vtables; i++) {
             int vt1 = bb.capacity() - vtables[i];
             int vt2 = space;
             short len = bb.getShort(vt1);

js/flatbuffers.js

@@ -604,23 +604,28 @@ flatbuffers.Builder.prototype.endObject = function() {
   this.addInt32(0);
   var vtableloc = this.offset();
 
+  // Trim trailing zeroes.
+  var i = this.vtable_in_use - 1;
+  for (; i >= 0 && this.vtable[i] == 0; i--) {}
+  var trimmed_size = i + 1;
+
   // Write out the current vtable.
-  for (var i = this.vtable_in_use - 1; i >= 0; i--) {
+  for (; i >= 0; i--) {
     // Offset relative to the start of the table.
     this.addInt16(this.vtable[i] != 0 ? vtableloc - this.vtable[i] : 0);
   }
 
   var standard_fields = 2; // The fields below:
   this.addInt16(vtableloc - this.object_start);
-  this.addInt16((this.vtable_in_use + standard_fields) * flatbuffers.SIZEOF_SHORT);
+  var len = (trimmed_size + standard_fields) * flatbuffers.SIZEOF_SHORT;
+  this.addInt16(len);
 
   // Search for an existing vtable that matches the current one.
   var existing_vtable = 0;
+  var vt1 = this.space;
 outer_loop:
-  for (var i = 0; i < this.vtables.length; i++) {
-    var vt1 = this.bb.capacity() - this.vtables[i];
-    var vt2 = this.space;
-    var len = this.bb.readInt16(vt1);
+  for (i = 0; i < this.vtables.length; i++) {
+    var vt2 = this.bb.capacity() - this.vtables[i];
     if (len == this.bb.readInt16(vt2)) {
       for (var j = flatbuffers.SIZEOF_SHORT; j < len; j += flatbuffers.SIZEOF_SHORT) {
         if (this.bb.readInt16(vt1 + j) != this.bb.readInt16(vt2 + j)) {

net/FlatBuffers/FlatBufferBuilder.cs

@@ -500,7 +500,11 @@ namespace FlatBuffers
             AddInt((int)0);
             var vtableloc = Offset;
             // Write out the current vtable.
-            for (int i = _vtableSize - 1; i >= 0 ; i--) {
+            int i = _vtableSize - 1;
+            // Trim trailing zeroes.
+            for (; i >= 0 && _vtable[i] == 0; i--) {}
+            int trimmedSize = i + 1;
+            for (; i >= 0 ; i--) {
                 // Offset relative to the start of the table.
                 short off = (short)(_vtable[i] != 0
                                         ? vtableloc - _vtable[i]
@@ -513,12 +517,12 @@ namespace FlatBuffers
 
             const int standardFields = 2; // The fields below:
             AddShort((short)(vtableloc - _objectStart));
-            AddShort((short)((_vtableSize + standardFields) *
+            AddShort((short)((trimmedSize + standardFields) *
                              sizeof(short)));
 
             // Search for an existing vtable that matches the current one.
             int existingVtable = 0;
-            for (int i = 0; i < _numVtables; i++) {
+            for (i = 0; i < _numVtables; i++) {
                 int vt1 = _bb.Length - _vtables[i];
                 int vt2 = _space;
                 short len = _bb.GetShort(vt1);

php/FlatbufferBuilder.php

@@ -596,7 +596,7 @@ class FlatbufferBuilder
         if (function_exists('mb_detect_encoding')) {
             return (bool) mb_detect_encoding($bytes, 'UTF-8', true);
         }
-    
+
         $len = strlen($bytes);
         if ($len < 1) {
             /* NOTE: always return 1 when passed string is null */
@@ -812,14 +812,18 @@ class FlatbufferBuilder
         $this->addInt(0);
         $vtableloc = $this->offset();
 
-        for ($i = $this->vtable_in_use -1; $i >= 0; $i--) {
+        $i = $this->vtable_in_use -1;
+        // Trim trailing zeroes.
+        for (; $i >= 0 && $this->vtable[$i] == 0; $i--) {}
+        $trimmed_size = $i + 1;
+        for (; $i >= 0; $i--) {
             $off = ($this->vtable[$i] != 0) ? $vtableloc - $this->vtable[$i] : 0;
             $this->addShort($off);
         }
 
         $standard_fields = 2; // the fields below
         $this->addShort($vtableloc - $this->object_start);
-        $this->addShort(($this->vtable_in_use + $standard_fields) * Constants::SIZEOF_SHORT);
+        $this->addShort(($trimmed_size + $standard_fields) * Constants::SIZEOF_SHORT);
 
         // search for an existing vtable that matches the current one.
         $existing_vtable = 0;

python/flatbuffers/builder.py

@@ -193,6 +193,10 @@ class Builder(object):
         objectOffset = self.Offset()
         existingVtable = None
 
+        # Trim trailing 0 offsets.
+        while self.current_vtable and self.current_vtable[-1] == 0:
+            self.current_vtable.pop()
+
         # Search backwards through existing vtables, because similar vtables
         # are likely to have been recently appended. See
         # BenchmarkVtableDeduplication for a case in which this heuristic

samples/monster_generated.h

@@ -316,7 +316,7 @@ struct MonsterBuilder {
   }
   MonsterBuilder &operator=(const MonsterBuilder &);
   flatbuffers::Offset<Monster> Finish() {
-    const auto end = fbb_.EndTable(start_, 10);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Monster>(end);
     return o;
   }
@@ -426,7 +426,7 @@ struct WeaponBuilder {
   }
   WeaponBuilder &operator=(const WeaponBuilder &);
   flatbuffers::Offset<Weapon> Finish() {
-    const auto end = fbb_.EndTable(start_, 2);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Weapon>(end);
     return o;
   }

src/idl_gen_cpp.cpp

@@ -1531,9 +1531,8 @@ class CppGenerator : public BaseGenerator {
              "(const {{STRUCT_NAME}}Builder &);";
 
     // Finish() function.
-    auto num_fields = NumToString(struct_def.fields.vec.size());
     code_ += "  flatbuffers::Offset<{{STRUCT_NAME}}> Finish() {";
-    code_ += "    const auto end = fbb_.EndTable(start_, " + num_fields + ");";
+    code_ += "    const auto end = fbb_.EndTable(start_);";
     code_ += "    auto o = flatbuffers::Offset<{{STRUCT_NAME}}>(end);";
 
     for (auto it = struct_def.fields.vec.begin();

src/idl_parser.cpp

@@ -1071,8 +1071,7 @@ CheckedError Parser::ParseTable(const StructDef &struct_def, std::string *value,
     builder_.PopBytes(struct_def.bytesize);
     assert(!ovalue);
   } else {
-    auto val = builder_.EndTable(start,
-                          static_cast<voffset_t>(struct_def.fields.vec.size()));
+    auto val = builder_.EndTable(start);
     if (ovalue) *ovalue = val;
     if (value) *value = NumToString(val);
   }

src/reflection.cpp

@@ -481,7 +481,7 @@ Offset<const Table *> CopyTable(FlatBufferBuilder &fbb,
     fbb.ClearOffsets();
     return fbb.EndStruct();
   } else {
-    return fbb.EndTable(start, static_cast<voffset_t>(fielddefs->size()));
+    return fbb.EndTable(start);
   }
 }
 

tests/FlatBuffers.Test/FlatBuffersFuzzTests.cs

@@ -205,11 +205,11 @@ namespace FlatBuffers.Test
             builder.EndObject();
             Assert.ArrayEqual(new byte[]
             {
-                0, 0, 0, 0, 0, 0, // padding to 16 bytes
-                6, 0, // vtable bytes
+                // No padding.
+                4, 0, // vtable bytes
                 4, 0, // end of object from here
-                0, 0, // entry 0 is empty (default value)
-                6, 0, 0, 0, // int32 offset for start of vtable
+                // entry 0 is not stored (trimmed end of vtable)
+                4, 0, 0, 0, // int32 offset for start of vtable
             },
                 builder.DataBuffer.Data);
         }

tests/GoTest.sh

@@ -30,6 +30,9 @@ mkdir -p ${go_src}/github.com/google/flatbuffers/go
 mkdir -p ${go_src}/flatbuffers_test
 
 cp -a MyGame/Example/*.go ./go_gen/src/MyGame/Example/
+# do not compile the gRPC generated files, which are not tested by go_test.go
+# below, but have their own test.
+rm ./go_gen/src/MyGame/Example/*_grpc.go
 cp -a ../go/* ./go_gen/src/github.com/google/flatbuffers/go
 cp -a ./go_test.go ./go_gen/src/flatbuffers_test/
 

tests/go_test.go

@@ -715,10 +715,10 @@ func CheckByteLayout(fail func(string, ...interface{})) {
 	b.PrependBoolSlot(0, false, false)
 	b.EndObject()
 	check([]byte{
-		6, 0, // vtable bytes
+		4, 0, // vtable bytes
 		4, 0, // end of object from here
-		0, 0, // entry 1 is zero
-		6, 0, 0, 0, // offset for start of vtable (int32)
+		// entry 1 is zero and not stored.
+		4, 0, 0, 0, // offset for start of vtable (int32)
 	})
 
 	// test 10: vtable with one int16
@@ -1085,7 +1085,6 @@ func CheckManualBuild(fail func(string, ...interface{})) ([]byte, flatbuffers.UO
 	b.PrependByteSlot(7, 1, 0)
 	b.PrependUOffsetTSlot(8, mon2, 0)
 	b.PrependUOffsetTSlot(9, test4, 0)
-	b.PrependUOffsetTSlot(9, test5, 0)
 	mon := b.EndObject()
 
 	b.Finish(mon)

tests/monster_test_generated.h

@@ -345,7 +345,7 @@ struct MonsterBuilder {
   }
   MonsterBuilder &operator=(const MonsterBuilder &);
   flatbuffers::Offset<Monster> Finish() {
-    const auto end = fbb_.EndTable(start_, 0);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Monster>(end);
     return o;
   }
@@ -404,7 +404,7 @@ struct TestSimpleTableWithEnumBuilder {
   }
   TestSimpleTableWithEnumBuilder &operator=(const TestSimpleTableWithEnumBuilder &);
   flatbuffers::Offset<TestSimpleTableWithEnum> Finish() {
-    const auto end = fbb_.EndTable(start_, 1);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<TestSimpleTableWithEnum>(end);
     return o;
   }
@@ -487,7 +487,7 @@ struct StatBuilder {
   }
   StatBuilder &operator=(const StatBuilder &);
   flatbuffers::Offset<Stat> Finish() {
-    const auto end = fbb_.EndTable(start_, 3);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Stat>(end);
     return o;
   }
@@ -1015,7 +1015,7 @@ struct MonsterBuilder {
   }
   MonsterBuilder &operator=(const MonsterBuilder &);
   flatbuffers::Offset<Monster> Finish() {
-    const auto end = fbb_.EndTable(start_, 34);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Monster>(end);
     fbb_.Required(o, Monster::VT_NAME);
     return o;
@@ -1352,7 +1352,7 @@ struct TypeAliasesBuilder {
   }
   TypeAliasesBuilder &operator=(const TypeAliasesBuilder &);
   flatbuffers::Offset<TypeAliases> Finish() {
-    const auto end = fbb_.EndTable(start_, 12);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<TypeAliases>(end);
     return o;
   }

tests/namespace_test/namespace_test1_generated.h

@@ -105,7 +105,7 @@ struct TableInNestedNSBuilder {
   }
   TableInNestedNSBuilder &operator=(const TableInNestedNSBuilder &);
   flatbuffers::Offset<TableInNestedNS> Finish() {
-    const auto end = fbb_.EndTable(start_, 1);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<TableInNestedNS>(end);
     return o;
   }

tests/namespace_test/namespace_test2_generated.h

@@ -76,7 +76,7 @@ struct TableInFirstNSBuilder {
   }
   TableInFirstNSBuilder &operator=(const TableInFirstNSBuilder &);
   flatbuffers::Offset<TableInFirstNS> Finish() {
-    const auto end = fbb_.EndTable(start_, 3);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<TableInFirstNS>(end);
     return o;
   }
@@ -140,7 +140,7 @@ struct TableInCBuilder {
   }
   TableInCBuilder &operator=(const TableInCBuilder &);
   flatbuffers::Offset<TableInC> Finish() {
-    const auto end = fbb_.EndTable(start_, 2);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<TableInC>(end);
     return o;
   }
@@ -190,7 +190,7 @@ struct SecondTableInABuilder {
   }
   SecondTableInABuilder &operator=(const SecondTableInABuilder &);
   flatbuffers::Offset<SecondTableInA> Finish() {
-    const auto end = fbb_.EndTable(start_, 1);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<SecondTableInA>(end);
     return o;
   }

tests/py_test.py

@@ -490,10 +490,10 @@ class TestByteLayout(unittest.TestCase):
         b.PrependBoolSlot(0, False, False)
         b.EndObject()
         self.assertBuilderEquals(b, [
-            6, 0,  # vtable bytes
+            4, 0,  # vtable bytes
             4, 0,  # end of object from here
-            0, 0,  # entry 1 is zero
-            6, 0, 0, 0,  # offset for start of vtable (int32)
+            # entry 1 is zero and not stored
+            4, 0, 0, 0,  # offset for start of vtable (int32)
         ])
 
     def test_vtable_with_one_int16(self):

tests/test.cpp

@@ -863,7 +863,7 @@ void FuzzTest1() {
         case 10: builder.AddElement<double  >(off, double_val, 0); break;
       }
     }
-    objects[i] = builder.EndTable(start, fields_per_object);
+    objects[i] = builder.EndTable(start);
   }
   builder.PreAlign<flatbuffers::largest_scalar_t>(0);  // Align whole buffer.
 

tests/union_vector/union_vector_generated.h

@@ -196,7 +196,7 @@ struct AttackerBuilder {
   }
   AttackerBuilder &operator=(const AttackerBuilder &);
   flatbuffers::Offset<Attacker> Finish() {
-    const auto end = fbb_.EndTable(start_, 1);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Attacker>(end);
     return o;
   }
@@ -309,7 +309,7 @@ struct MovieBuilder {
   }
   MovieBuilder &operator=(const MovieBuilder &);
   flatbuffers::Offset<Movie> Finish() {
-    const auto end = fbb_.EndTable(start_, 4);
+    const auto end = fbb_.EndTable(start_);
     auto o = flatbuffers::Offset<Movie>(end);
     return o;
   }