diff --git a/src/IceGlobalContext.cpp b/src/IceGlobalContext.cpp
index 745f0d4..5f9b620 100644
--- a/src/IceGlobalContext.cpp
+++ b/src/IceGlobalContext.cpp
@@ -120,7 +120,8 @@
                              IceString TestPrefix, const ClFlags &Flags)
     : StrDump(OsDump), StrEmit(OsEmit), VMask(Mask),
       ConstPool(new ConstantPool()), Arch(Arch), Opt(Opt),
-      TestPrefix(TestPrefix), Flags(Flags), HasEmittedFirstMethod(false) {}
+      TestPrefix(TestPrefix), Flags(Flags), HasEmittedFirstMethod(false),
+      RNG("") {}
 
 // Scan a string for S[0-9A-Z]*_ patterns and replace them with
 // S<num>_ where <num> is the next base-36 value.  If a type name