Merge pull request #69710 from Azoy/stdlib-warning-cleanup

[stdlib] Silence some standard library warnings

Author: Azoy

lib/ASTGen/Sources/ASTGen/Macros.swift

@@ -255,6 +255,20 @@ func checkMacroDefinition(
         case "ExternalMacro":
           return Int(BridgedMacroDefinitionKind.builtinExternalMacro.rawValue)
 
+        // These builtins don't exist, but are put into the standard library at
+        // least for documentation purposes right now. Don't emit a warning for
+        // them, but do fail operation.
+        case "FileIDMacro",
+             "FilePathMacro",
+             "FileMacro",
+             "FunctionMacro",
+             "LineMacro",
+             "ColumnMacro",
+             "DSOHandleMacro",
+             "WarningMacro",
+             "ErrorMacro":
+          return -1
+
         default:
           // Warn about the unknown builtin.
           let srcMgr = SourceManager(cxxDiagnosticEngine: diagEnginePtr)

lib/Sema/TypeCheckDeclPrimary.cpp

@@ -2030,6 +2030,17 @@ static void checkProtocolRefinementRequirements(ProtocolDecl *proto) {
       // TODO(kavon): emit tailored error diagnostic to remove the ~Copyable
     }
 
+    // SIMDScalar in the standard library currently emits this warning for:
+    // 'Hashable', 'Encodable', and 'Decodable'. This is unfortunate, but we
+    // cannot fix it as it would alter the ABI of the protocol. Silence these
+    // warnings specifically for those cases.
+    if (proto->isSpecificProtocol(KnownProtocolKind::SIMDScalar) &&
+        (otherProto->isSpecificProtocol(KnownProtocolKind::Hashable) ||
+        otherProto->isSpecificProtocol(KnownProtocolKind::Encodable) ||
+        otherProto->isSpecificProtocol(KnownProtocolKind::Decodable))) {
+      continue;
+    }
+
     // GenericSignature::getRequiredProtocols() canonicalizes the protocol
     // list by dropping protocols that are inherited by other protocols in
     // the list. Any protocols that remain in the list other than 'proto'

stdlib/public/core/Macros.swift

@@ -71,4 +71,4 @@ public macro warning(_ message: String) = Builtin.WarningMacro
 @freestanding(declaration)
 public macro error(_ message: String) = Builtin.ErrorMacro
 
-#endif
+#endif // $Macros && hasAttribute(attached)