Parse: Address an llvm_unreachable that is actually reachable

Author: slavapestov

lib/Parse/ParseDecl.cpp

@@ -6337,8 +6337,8 @@ ParserStatus Parser::parseDecl(bool IsAtStartOfLineOrPreviousHadSemi,
           DescriptiveKind = DescriptiveDeclKind::StaticProperty;
           break;
         case StaticSpellingKind::KeywordClass:
-          llvm_unreachable("kw_class is only parsed as a modifier if it's "
-                           "followed by a keyword");
+          DescriptiveKind = DescriptiveDeclKind::ClassProperty;
+          break;
         }
 
         diagnose(Tok.getLoc(), diag::expected_keyword_in_decl, "var",
@@ -6366,8 +6366,7 @@ ParserStatus Parser::parseDecl(bool IsAtStartOfLineOrPreviousHadSemi,
             DescriptiveKind = DescriptiveDeclKind::StaticMethod;
             break;
           case StaticSpellingKind::KeywordClass:
-            llvm_unreachable("kw_class is only parsed as a modifier if it's "
-                             "followed by a keyword");
+            DescriptiveKind = DescriptiveDeclKind::ClassMethod;
           }
         }
 

validation-test/compiler_crashers_2/1c4f5ed8bb743453.swift renamed to validation-test/compiler_crashers_2_fixed/1c4f5ed8bb743453.swift

@@ -1,4 +1,4 @@
 // {"signature":"swift::Parser::parseNewDeclAttribute(swift::DeclAttributes&, swift::SourceLoc, swift::DeclAttrKind, bool)::$_4::operator()() const"}
-// RUN: not --crash %target-swift-frontend -typecheck %s
+// RUN: not %target-swift-frontend -typecheck %s
 class a {
   class override b

validation-test/compiler_crashers_2/1fb63f2dc87bc9b9.swift renamed to validation-test/compiler_crashers_2_fixed/1fb63f2dc87bc9b9.swift

@@ -1,3 +1,3 @@
 // {"signature":"swift::Parser::parseDecl(bool, bool, llvm::function_ref<void (swift::Decl*)>, bool)"}
-// RUN: not --crash %target-swift-frontend -typecheck %s
+// RUN: not %target-swift-frontend -typecheck %s
 class a { class override ( override