Reflection: Add an unreachable() function instead of doing assert(false && ...

Author: slavapestov

stdlib/public/Reflection/TypeLowering.cpp

@@ -24,6 +24,12 @@
 
 #include <iostream>
 
+[[noreturn]]
+static void unreachable(const char *Message) {
+  std::cerr << "fatal error: " << Message << "\n";
+  std::abort();
+}
+
 using namespace swift;
 using namespace reflection;
 
@@ -167,7 +173,7 @@ class PrintTypeInfo {
     }
     }
 
-    assert(false && "Bad TypeInfo kind");
+    unreachable("Bad TypeInfo kind");
   }
 };
 
@@ -675,13 +681,13 @@ class HasSingletonMetatype
 
   MetatypeRepresentation
   visitGenericTypeParameterTypeRef(const GenericTypeParameterTypeRef *GTP) {
-    assert(false && "Must have concrete TypeRef");
+    unreachable("Must have concrete TypeRef");
     return MetatypeRepresentation::Unknown;
   }
 
   MetatypeRepresentation
   visitDependentMemberTypeRef(const DependentMemberTypeRef *DM) {
-    assert(false && "Must have concrete TypeRef");
+    unreachable("Must have concrete TypeRef");
     return MetatypeRepresentation::Unknown;
   }
 
@@ -893,13 +899,13 @@ class LowerType
 
   const TypeInfo *
   visitGenericTypeParameterTypeRef(const GenericTypeParameterTypeRef *GTP) {
-    assert(false && "Must have concrete TypeRef");
+    unreachable("Must have concrete TypeRef");
     return nullptr;
   }
 
   const TypeInfo *
   visitDependentMemberTypeRef(const DependentMemberTypeRef *DM) {
-    assert(false && "Must have concrete TypeRef");
+    unreachable("Must have concrete TypeRef");
     return nullptr;
   }
 
@@ -980,7 +986,7 @@ class LowerType
   }
 
   const TypeInfo *visitOpaqueTypeRef(const OpaqueTypeRef *O) {
-    assert(false && "Can't lower opaque TypeRef");
+    unreachable("Can't lower opaque TypeRef");
     return nullptr;
   }
 };

stdlib/public/Reflection/TypeRef.cpp

@@ -22,6 +22,12 @@
 using namespace swift;
 using namespace reflection;
 
+[[noreturn]]
+static void unreachable(const char *Message) {
+  std::cerr << "fatal error: " << Message << "\n";
+  std::abort();
+}
+
 class PrintTypeRef : public TypeRefVisitor<PrintTypeRef, void> {
   std::ostream &OS;
   unsigned Indent;
@@ -354,7 +360,7 @@ unsigned NominalTypeTrait::getDepth() const {
     case TypeRefKind::BoundGeneric:
       return 1 + cast<BoundGenericTypeRef>(P)->getDepth();
     default:
-      assert(false && "Asked for depth on non-nominal typeref");
+      unreachable("Asked for depth on non-nominal typeref");
     }
   }
 
@@ -663,7 +669,7 @@ class TypeRefSubstitution
       break;
     }
     default:
-      assert(false && "Unknown base type");
+      unreachable("Unknown base type");
     }
 
     assert(TypeWitness);