[Parse/Sema] Diagnose invalid attributes for ParamDecl

Previously, invalid attributes were silently accepted and ignored.

https://bugs.swift.org/browse/SR-8202

Author: rintaro

include/swift/AST/Attr.def

@@ -265,7 +265,7 @@ DECL_ATTR(__raw_doc_comment, RawDocComment,
   RejectByParser |
   NotSerialized, 48)
 CONTEXTUAL_DECL_ATTR(weak, ReferenceOwnership,
-  OnVar | OnParam |
+  OnVar |
   DeclModifier |
   NotSerialized, 49)
 CONTEXTUAL_DECL_ATTR_ALIAS(unowned, ReferenceOwnership)

lib/Parse/ParsePattern.cpp

@@ -430,7 +430,7 @@ mapParsedParameters(Parser &parser,
                                      argNameLoc, argName,
                                      paramNameLoc, paramName, Type(),
                                      parser.CurDeclContext);
-
+    param->getAttrs() = paramInfo.Attrs;
     bool parsingEnumElt
       = (paramContext == Parser::ParameterContextKind::EnumElement);
     // If we're not parsing an enum case, lack of a SourceLoc for both

lib/Sema/TypeCheckPattern.cpp

@@ -828,6 +828,8 @@ bool TypeChecker::typeCheckParameterList(ParameterList *PL, DeclContext *DC,
   bool hadError = false;
 
   for (auto param : *PL) {
+    checkDeclAttributesEarly(param);
+
     auto typeRepr = param->getTypeLoc().getTypeRepr();
     if (!typeRepr &&
         param->hasInterfaceType()) {

test/Parse/invalid.swift

@@ -144,3 +144,9 @@ let x: () = ()
 !(()) // expected-error {{cannot convert value of type '()' to expected argument type 'Bool'}}
 !(x) // expected-error {{cannot convert value of type '()' to expected argument type 'Bool'}}
 !x // expected-error {{cannot convert value of type '()' to expected argument type 'Bool'}}
+
+func sr8202_foo(@NSApplicationMain x: Int) {} // expected-error {{@NSApplicationMain may only be used on 'class' declarations}}
+func sr8202_bar(@available(iOS, deprecated: 0) x: Int) {} // expected-error {{'@availability' attribute cannot be applied to this declaration}}
+func sr8202_baz(@discardableResult x: Int) {} // expected-error {{'@discardableResult' attribute cannot be applied to this declaration}}
+func sr8202_qux(@objcMembers x: String) {} // expected-error {{@objcMembers may only be used on 'class' declarations}}
+func sr8202_quux(@weak x: String) {} // expected-error {{'weak' is a declaration modifier, not an attribute}} expected-error {{'weak' may only be used on 'var' declarations}}