[core] Bracket init works for optional<T> in GCC 4.9

3 files changed, 7 insertions, 7 deletions

diff --git a/include/mbgl/renderer/query.hpp b/include/mbgl/renderer/query.hpp
index b9d5f21a44..4cadf4f017 100644
--- a/include/mbgl/renderer/query.hpp
+++ b/include/mbgl/renderer/query.hpp
@@ -13,8 +13,8 @@ namespace mbgl {
  */
 class RenderedQueryOptions {
 public:
-    RenderedQueryOptions(optional<std::vector<std::string>> layerIDs_ = optional<std::vector<std::string>>(),
-                         optional<style::Filter> filter_ = optional<style::Filter>())
+    RenderedQueryOptions(optional<std::vector<std::string>> layerIDs_ = {},
+                         optional<style::Filter> filter_ = {})
         : layerIDs(std::move(layerIDs_)),
           filter(std::move(filter_)) {}
 
@@ -29,8 +29,8 @@ public:
  */
 class SourceQueryOptions {
 public:
-    SourceQueryOptions(optional<std::vector<std::string>> sourceLayers_ = optional<std::vector<std::string>> (),
-                       optional<style::Filter> filter_ = optional<style::Filter>())
+    SourceQueryOptions(optional<std::vector<std::string>> sourceLayers_ = {},
+                       optional<style::Filter> filter_ = {})
         : sourceLayers(std::move(sourceLayers_)),
           filter(std::move(filter_)) {}
 
diff --git a/include/mbgl/renderer/renderer.hpp b/include/mbgl/renderer/renderer.hpp
index c209e03045..083102acbe 100644
--- a/include/mbgl/renderer/renderer.hpp
+++ b/include/mbgl/renderer/renderer.hpp
@@ -26,7 +26,7 @@ class Renderer {
 public:
     Renderer(RendererBackend&, float pixelRatio_, FileSource&, Scheduler&,
              GLContextMode = GLContextMode::Unique,
-             const optional<std::string> programCacheDir = optional<std::string>());
+             const optional<std::string> programCacheDir = {});
     ~Renderer();
 
     void setObserver(RendererObserver*);
diff --git a/include/mbgl/style/transition_options.hpp b/include/mbgl/style/transition_options.hpp
index 0ac7c02c6b..87a81717a0 100644
--- a/include/mbgl/style/transition_options.hpp
+++ b/include/mbgl/style/transition_options.hpp
@@ -11,8 +11,8 @@ public:
     optional<Duration> duration;
     optional<Duration> delay;
 
-    TransitionOptions(optional<Duration> duration_ = optional<Duration>(),
-                      optional<Duration> delay_ = optional<Duration>())
+    TransitionOptions(optional<Duration> duration_ = {},
+                      optional<Duration> delay_ = {})
         : duration(std::move(duration_)),
           delay(std::move(delay_)) {}