Avoid aggregate initialization syntax in places where C++11 doesn't allow it

src/compiler/build_tables/build_parse_table.cc

@@ -73,15 +73,14 @@ class ParseTableBuilder {
     Symbol start_symbol = grammar.variables.empty() ?
       Symbol::terminal(0) :
       Symbol::non_terminal(0);
-    Production start_production{
-      vector<ProductionStep>(1, ProductionStep{
-        start_symbol,
-        0,
-        rules::AssociativityNone,
-        rules::Alias{}
-      }),
-      0
-    };
+
+    Production start_production;
+    start_production.steps.push_back({
+      start_symbol,
+      0,
+      rules::AssociativityNone,
+      rules::Alias{}
+    });
 
     add_parse_state({}, ParseItemSet{{
       {

src/compiler/build_tables/parse_item_set_builder.cc

@@ -208,16 +208,17 @@ const vector<Production> &ParseItemSetBuilder::inline_production(const ParseItem
     auto end = item.production->steps.end();
     auto step = begin + item.step_index;
 
-    Production production{
-      vector<ProductionStep>(begin, step),
-      item.production->dynamic_precedence
-    };
+    Production production;
+    production.steps.assign(begin, step);
+    production.dynamic_precedence = item.production->dynamic_precedence;
+
     for (auto &step : *production_to_insert) {
       production.steps.push_back(step);
       if (!inlined_step.alias.value.empty()) {
         production.steps.back().alias = inlined_step.alias;
       }
     }
+
     production.back().precedence = inlined_step.precedence;
     production.back().associativity = inlined_step.associativity;
     production.steps.insert(

src/compiler/rules/metadata.cc

@@ -93,7 +93,8 @@ Metadata Metadata::main_token(const Rule &rule) {
 
 Metadata Metadata::alias(string &&value, bool is_named, const Rule &rule) {
   MetadataParams params;
-  params.alias = {move(value), is_named};
+  params.alias.value = move(value);
+  params.alias.is_named = is_named;
   return Metadata{rule, params};
 }