Add an easy "reserve" call to symbol sorting.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/mbgl/renderer/buckets/symbol_bucket.cpp b/src/mbgl/renderer/buckets/symbol_bucket.cpp
index ebcf93f2b1..60e8a0b504 100644
--- a/src/mbgl/renderer/buckets/symbol_bucket.cpp
+++ b/src/mbgl/renderer/buckets/symbol_bucket.cpp
@@ -179,6 +179,7 @@ void SymbolBucket::sortFeatures(const float angle) {
 
     // To avoid sorting the actual symbolInstance array we sort an array of indexes.
     std::vector<size_t> symbolInstanceIndexes;
+    symbolInstanceIndexes.reserve(symbolInstances.size());
     for (size_t i = 0; i < symbolInstances.size(); i++) {
         symbolInstanceIndexes.push_back(i);
     }