From 8d0d5df67909e7c992618cc87b66dea17502da87 Mon Sep 17 00:00:00 2001
From: Sven Konietzny <svenk.public@gmail.com>
Date: Fri, 14 Jun 2019 08:06:46 +0200
Subject: [PATCH] Optimizations

---
 src/idl_gen_cpp.cpp     | 44 +++++++++++++++++------------------------
 src/idl_gen_general.cpp |  2 +-
 src/idl_parser.cpp      |  5 +++--
 3 files changed, 22 insertions(+), 29 deletions(-)

diff --git a/src/idl_gen_cpp.cpp b/src/idl_gen_cpp.cpp
index 4238a26f757c..1325e067dc90 100644
--- a/src/idl_gen_cpp.cpp
+++ b/src/idl_gen_cpp.cpp
@@ -307,31 +307,13 @@ class CppGenerator : public BaseGenerator {
       }
     }
 
-    // Check if enum arrays are used without specifying --scoped-enums
-    if (!parser_.opts.scoped_enums) {
-      for (auto it_s = parser_.structs_.vec.begin();
-           it_s != parser_.structs_.vec.end(); ++it_s) {
-        const auto &struct_def = **it_s;
-        for (auto it_f = struct_def.fields.vec.begin();
-             it_f != struct_def.fields.vec.end(); ++it_f) {
-          const auto &field_def = **it_f;
-          const auto &field_type = field_def.value.type;
-
-          if (IsArray(field_type) && IsEnum(field_type.VectorType())) {
-            printf("--scoped-enums must be enabled to use enum arrays\n");
-            return false;
-          }
-        }
-      }
-    }
-
     // Generate code for all structs, then all tables.
     for (auto it = parser_.structs_.vec.begin();
          it != parser_.structs_.vec.end(); ++it) {
       const auto &struct_def = **it;
       if (struct_def.fixed && !struct_def.generated) {
         SetNameSpace(struct_def.defined_namespace);
-        GenStruct(struct_def);
+        if (!GenStruct(struct_def)) return false;
       }
     }
     for (auto it = parser_.structs_.vec.begin();
@@ -2724,7 +2706,7 @@ class CppGenerator : public BaseGenerator {
   }
 
   // Generate an accessor struct with constructor for a flatbuffers struct.
-  void GenStruct(const StructDef &struct_def) {
+  bool GenStruct(const StructDef &struct_def) {
     // Generate an accessor struct, with private variables of the form:
     // type name_;
     // Generates manual padding and alignment.
@@ -2743,13 +2725,21 @@ class CppGenerator : public BaseGenerator {
     for (auto it = struct_def.fields.vec.begin();
          it != struct_def.fields.vec.end(); ++it) {
       const auto &field = **it;
-      code_.SetValue("FIELD_TYPE",
-                     GenTypeGet(field.value.type, " ", "", " ", false));
+      const auto &field_type = field.value.type;
+
+      // Check if enum arrays are used without specifying --scoped-enums
+      if (!parser_.opts.scoped_enums && IsArray(field_type) &&
+          IsEnum(field_type.VectorType())) {
+        printf("--scoped-enums must be enabled to use enum arrays\n");
+        return false;
+      }
+
+      code_.SetValue("FIELD_TYPE", GenTypeGet(field_type, " ", "", " ", false));
       code_.SetValue("FIELD_NAME", Name(field));
-      code_.SetValue(
-          "ARRAY", IsArray(field.value.type)
-                       ? "[" + NumToString(field.value.type.fixed_length) + "]"
-                       : "");
+      code_.SetValue("ARRAY",
+                     IsArray(field_type)
+                         ? "[" + NumToString(field_type.fixed_length) + "]"
+                         : "");
       code_ += ("  {{FIELD_TYPE}}{{FIELD_NAME}}_{{ARRAY}};");
 
       if (field.padding) {
@@ -2925,6 +2915,8 @@ class CppGenerator : public BaseGenerator {
     code_ += "FLATBUFFERS_STRUCT_END({{STRUCT_NAME}}, {{STRUCT_BYTE_SIZE}});";
     if (parser_.opts.gen_compare) GenCompareOperator(struct_def, "()");
     code_ += "";
+
+    return true;
   }
 
   // Set up the correct namespace. Only open a namespace if the existing one is
diff --git a/src/idl_gen_general.cpp b/src/idl_gen_general.cpp
index e641223b9bfb..18059e17d726 100644
--- a/src/idl_gen_general.cpp
+++ b/src/idl_gen_general.cpp
@@ -1280,7 +1280,7 @@ class GeneralGenerator : public BaseGenerator {
       // Generate mutators for scalar fields or vectors of scalars.
       if (parser_.opts.mutable_buffer) {
         auto is_series = (IsSeries(field.value.type));
-        auto underlying_type =
+        const auto &underlying_type =
             is_series ? field.value.type.VectorType() : field.value.type;
         // Boolean parameters have to be explicitly converted to byte
         // representation.
diff --git a/src/idl_parser.cpp b/src/idl_parser.cpp
index 61b777ef834f..a5f3860c8d8b 100644
--- a/src/idl_parser.cpp
+++ b/src/idl_parser.cpp
@@ -1285,7 +1285,8 @@ CheckedError Parser::ParseArray(Value &array) {
 
   uoffset_t count = 0;
   auto err = ParseVectorDelimiters(count, [&](uoffset_t &) -> CheckedError {
-    Value val;
+    vector_emplace_back(&stack, Value());
+    auto &val = stack.back();
     val.type = type;
     if (IsStruct(type)) {
       ECHECK(ParseTable(*val.type.struct_def, &val.constant, nullptr));
@@ -1299,7 +1300,7 @@ CheckedError Parser::ParseArray(Value &array) {
 
   if (length != count) return Error("Fixed-length array size is incorrect.");
 
-  for (auto it = stack.rbegin(); it != stack.rend(); it++) {
+  for (auto it = stack.rbegin(); it != stack.rend(); ++it) {
     auto &val = *it;
     // clang-format off
     switch (val.type.base_type) {