diff --git a/clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp b/clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp
index 8a02b2ca9613..2e3e9f51e7df 100644
--- a/clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp
+++ b/clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp
@@ -568,8 +568,10 @@ void ExprEngine::VisitInitListExpr(const InitListExpr *IE,
                                              state->getSVal(initEx, LCtx)));
     return;
   }
-  
-  llvm_unreachable("unprocessed InitListExpr type");
+
+  assert(IE->getNumInits() == 1);
+  B.generateNode(IE, Pred, state->BindExpr(IE, LCtx, UnknownVal()));
+  return;
 }
 
 void ExprEngine::VisitGuardedExpr(const Expr *Ex,
diff --git a/clang/test/Analysis/cxx11-crashes.cpp b/clang/test/Analysis/cxx11-crashes.cpp
index 6e60ac63cc3a..a7bfe4ebe5f5 100644
--- a/clang/test/Analysis/cxx11-crashes.cpp
+++ b/clang/test/Analysis/cxx11-crashes.cpp
@@ -31,3 +31,8 @@ void radar11487541() {
   namespace fs = boost::filesystem;
   fs::path p;
 }
+
+// PR12873 radrar://11499139
+void testFloatInitializer() {
+  const float ysize={0.015}, xsize={0.01};
+}