Add explicit keywords.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48801 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/ExecutionEngine/JIT/JITEmitter.cpp b/lib/ExecutionEngine/JIT/JITEmitter.cpp
index b675811..8d5a94a 100644
--- a/lib/ExecutionEngine/JIT/JITEmitter.cpp
+++ b/lib/ExecutionEngine/JIT/JITEmitter.cpp
@@ -96,7 +96,7 @@
 
     static JITResolver *TheJITResolver;
   public:
-    JITResolver(JIT &jit) : nextGOTIndex(0) {
+    explicit JITResolver(JIT &jit) : nextGOTIndex(0) {
       TheJIT = &jit;
 
       LazyResolverFn = jit.getJITInfo().getLazyResolverFunction(JITCompilerFn);