diff --git a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h
--- a/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h
+++ b/clang/include/clang/StaticAnalyzer/Core/PathSensitive/ConstraintManager.h
@@ -96,11 +96,7 @@
     // If StTrue is infeasible, asserting the falseness of Cond is unnecessary
     // because the existing constraints already establish this.
     if (!StTrue) {
-#ifndef __OPTIMIZE__
-      // This check is expensive and should be disabled even in Release+Asserts
-      // builds.
-      // FIXME: __OPTIMIZE__ is a GNU extension that Clang implements but MSVC
-      // does not. Is there a good equivalent there?
+#ifdef EXPENSIVE_CHECKS
       assert(assume(State, Cond, false) && "System is over constrained.");
 #endif
       return ProgramStatePair((ProgramStateRef)nullptr, State);