Fix enum structs not getting zero padding.

Bug: issue #995
Test: new test case

compiler/array-helpers.cpp

@@ -957,6 +957,7 @@ void CompoundEmitter::AddInlineEnumStruct(EnumStructDecl* es, ArrayExpr* array)
     auto field_list = &es->fields();
     auto field_iter = field_list->begin();
 
+    size_t start_pos = data_size();
     for (const auto& item : array->exprs()) {
         if (StringExpr* expr = item->as<StringExpr>()) {
             // Substrings can only appear in an enum struct. Normal 2D
@@ -981,6 +982,12 @@ void CompoundEmitter::AddInlineEnumStruct(EnumStructDecl* es, ArrayExpr* array)
         assert(field_iter != field_list->end());
         field_iter++;
     }
+
+    size_t emitted = data_size() - start_pos;
+    if (emitted < es->array_size())
+        pending_zeroes_ += es->array_size() - emitted;
+
+    assert(data_size() - start_pos == es->array_size());
 }
 
 void CompoundEmitter::AddInlineArray(LayoutFieldDecl* field, ArrayExpr* array) {

tests/enum-structs/zero-fill.out

@@ -0,0 +1,3 @@
+0, 1, 2, 0
+1, 4, 5, 6
+2, 7, 0, 0

tests/enum-structs/zero-fill.sp

@@ -0,0 +1,21 @@
+native void printnums(...);
+
+enum struct Numbers
+{
+	int first;
+	int second;
+	int third;
+}
+
+static Numbers list[] = {
+	{ 1, 2 },
+	{ 4, 5, 6 },
+	{ 7 },
+}
+
+public void main()
+{
+	for (int i = 0; i < sizeof(list); i++) {
+		printnums(i, list[i].first, list[i].second, list[i].third);
+	}
+}