diff --git a/SPIRV/SpvBuilder.cpp b/SPIRV/SpvBuilder.cpp
index c327d38f..6d1b2b92 100644
--- a/SPIRV/SpvBuilder.cpp
+++ b/SPIRV/SpvBuilder.cpp
@@ -1738,7 +1738,7 @@ void Builder::endSwitch(std::vector<Block*>& /*segmentBlock*/)
 // Comments in header
 void Builder::makeNewLoop(bool loopTestFirst)
 {
-    loops.push({ });
+    loops.push(Loop());
     Loop& loop = loops.top();
 
     loop.function  = &getBuildPoint()->getParent();
diff --git a/SPIRV/SpvBuilder.h b/SPIRV/SpvBuilder.h
index de7c3361..27ffd3ec 100644
--- a/SPIRV/SpvBuilder.h
+++ b/SPIRV/SpvBuilder.h
@@ -524,6 +524,7 @@ protected:
 
     // Data that needs to be kept in order to properly handle loops.
     struct Loop {
+        Loop() : header(nullptr), merge(nullptr), body(nullptr), testFirst(false), isFirstIteration(nullptr), function(nullptr) { }
         // The header is the first block generated for the loop.
         // It dominates all the blocks in the loop, i.e. it is always
         // executed before any others.