diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -16194,7 +16194,11 @@
           ED->setIntegerTypeSourceInfo(TI);
         else
           ED->setIntegerType(QualType(EnumUnderlying.get<const Type *>(), 0));
-        ED->setPromotionType(ED->getIntegerType());
+        QualType EnumTy = ED->getIntegerType();
+        if (EnumTy->isPromotableIntegerType())
+          ED->setPromotionType(Context.getPromotedIntegerType(EnumTy));
+        else
+          ED->setPromotionType(EnumTy);
       }
     } else { // struct/union
       New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name,
@@ -16816,8 +16820,12 @@
       if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>())
         ED->setIntegerTypeSourceInfo(TI);
       else
-        ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0));
-      ED->setPromotionType(ED->getIntegerType());
+        ED->setIntegerType(QualType(EnumUnderlying.get<const Type *>(), 0));
+      QualType EnumTy = ED->getIntegerType();
+      if (EnumTy->isPromotableIntegerType())
+        ED->setPromotionType(Context.getPromotedIntegerType(EnumTy));
+      else
+        ED->setPromotionType(EnumTy);
       assert(ED->isComplete() && "enum with type should be complete");
     }
   } else {
diff --git a/clang/test/SemaCXX/enum-bool.cpp b/clang/test/SemaCXX/enum-bool.cpp
new file mode 100644
--- /dev/null
+++ b/clang/test/SemaCXX/enum-bool.cpp
@@ -0,0 +1,8 @@
+// RUN: %clang_cc1  -fsyntax-only %s
+
+// This shouldn't crash.
+
+enum GH56560_1 : bool;
+bool GH56560_2(GH56560_1 a, GH56560_1 b) {
+    return a == b;
+}