Merge pull request #73722 from rintaro/6.0-macros-attachedmacro-decllocation

[6.0][Macros] Fix source location for declaration syntax of attached macros

Author: rintaro

lib/ASTGen/Sources/ASTGen/Macros.swift

@@ -888,7 +888,7 @@ func expandAttachedMacroIPC(
 
   let declSyntax = PluginMessage.Syntax(
     syntax: Syntax(declarationNode),
-    in: customAttrSourceFilePtr
+    in: declarationSourceFilePtr
   )!
 
   let parentDeclSyntax: PluginMessage.Syntax?

test/Macros/DebugDescription/error_complex_implementation.swift

@@ -2,6 +2,7 @@
 
 // RUN: %empty-directory(%t)
 // RUN: %target-swift-frontend %s -swift-version 5 -module-name main -disable-availability-checking -typecheck -verify -plugin-path %swift-plugin-dir
+// RUN: %target-swift-frontend %s -swift-version 5 -module-name main -disable-availability-checking -typecheck -verify -external-plugin-path %swift-plugin-dir#%swift-plugin-server
 
 @DebugDescription
 struct MyStruct {