SE-495: Make CImplementation an official feature

xymus · xymus · commit bce585c133f7 · 2025-10-29T11:55:51.000-07:00
diff --git a/include/swift/Basic/Features.def b/include/swift/Basic/Features.def
@@ -278,6 +278,7 @@ LANGUAGE_FEATURE(InoutLifetimeDependence, 0, "Support @_lifetime(&)")
 SUPPRESSIBLE_LANGUAGE_FEATURE(NonexhaustiveAttribute, 487, "Nonexhaustive Enums")
 LANGUAGE_FEATURE(ModuleSelector, 491, "Module selectors (`Module::name` syntax)")
 LANGUAGE_FEATURE(CDecl, 495, "C compatible functions and enums with @c")
+LANGUAGE_FEATURE(CImplementation, 495, "C compatible functions and enums with @c")
 
 // Swift 6
 UPCOMING_FEATURE(ConciseMagicFile, 274, 6)
@@ -470,9 +471,6 @@ EXPERIMENTAL_FEATURE(ClosureIsolation, true)
 // staging purposes.
 EXPERIMENTAL_FEATURE(ObjCImplementationWithResilientStorage, true)
 
-// Enable @implementation on @_cdecl functions.
-EXPERIMENTAL_FEATURE(CImplementation, true)
-
 // Enable @sensitive attribute.
 EXPERIMENTAL_FEATURE(Sensitive, true)
 
diff --git a/lib/Sema/TypeCheckDeclObjC.cpp b/lib/Sema/TypeCheckDeclObjC.cpp
@@ -4197,11 +4197,6 @@ class ObjCImplementationChecker {
         !decl->getASTContext().LangOpts.hasFeature(Feature::CImplementation))
       return;
 
-    // Only encourage @_objcImplementation *extension* adopters to adopt
-    // @implementation; @_objcImplementation @_cdecl hasn't been stabilized yet.
-    if (!isa<ExtensionDecl>(decl))
-      return;
-
     auto diag = diagnose(getAttr()->getLocation(),
                          diag::objc_implementation_early_spelling_deprecated);
     diag.fixItReplace(getAttr()->getRangeWithAt(), "@implementation");
diff --git a/test/decl/ext/cdecl_implementation_features.swift b/test/decl/ext/cdecl_implementation_features.swift
@@ -1,15 +1,13 @@
-// RUN: not %target-swift-frontend(mock-sdk: %clang-importer-sdk-nosource) -typecheck %s -import-objc-header %S/Inputs/objc_implementation.h 2>&1 | %FileCheck --check-prefixes NO,CHECK %s
-// RUN: not %target-swift-frontend(mock-sdk: %clang-importer-sdk-nosource) -typecheck %s -import-objc-header %S/Inputs/objc_implementation.h -enable-experimental-feature CImplementation 2>&1 | %FileCheck --check-prefixes YES,C,CHECK %s
+// RUN: not %target-swift-frontend(mock-sdk: %clang-importer-sdk-nosource) -typecheck %s -import-objc-header %S/Inputs/objc_implementation.h > %t 2>&1
+// RUN: %FileCheck --input-file %t --check-prefixes YES,CHECK %s
+// RUN: not %target-swift-frontend(mock-sdk: %clang-importer-sdk-nosource) -typecheck %s -import-objc-header %S/Inputs/objc_implementation.h -enable-experimental-feature CImplementation > %t 2>&1
+// RUN: %FileCheck --input-file %t --check-prefixes YES,C,CHECK %s
 
 // REQUIRES: swift_feature_CImplementation
 
-// YES-DAG: cdecl_implementation_features.swift:[[@LINE+4]]:{{[0-9]+}}: warning: global function 'CImplFunc1' of type '(Double) -> ()' does not match type '(Int32) -> Void' declared by the header; this will become an error after adopting '@implementation'
-// NO-DAG: cdecl_implementation_features.swift:[[@LINE+3]]:{{[0-9]+}}: error: '_objcImplementation' attribute is only valid when experimental feature CImplementation is enabled
-// YES-NOT: cdecl_implementation_features.swift:[[@LINE+2]]:{{[0-9]+}}: warning: '@_objcImplementation' is deprecated; use '@implementation' instead
-// TODO: When @implementation @_cdecl stabilizes, YES-NOT on the line above will become YES-DAG
+// YES-DAG: cdecl_implementation_features.swift:[[@LINE+1]]:{{[0-9]+}}: warning: global function 'CImplFunc1' of type '(Double) -> ()' does not match type '(Int32) -> Void' declared by the header; this will become an error after adopting '@implementation'
 @_objcImplementation @_cdecl("CImplFunc1") func CImplFunc1(_: Double) {}
 
-// YES-DAG: cdecl_implementation_features.swift:[[@LINE+3]]:{{[0-9]+}}: error: global function 'CImplFunc2' of type '(Double) -> ()' does not match type '(Int32) -> Void' declared by the header{{$}}
-// NO-DAG: cdecl_implementation_features.swift:[[@LINE+2]]:{{[0-9]+}}: error: 'implementation' attribute is only valid when experimental feature CImplementation is enabled
+// YES-DAG: cdecl_implementation_features.swift:[[@LINE+2]]:{{[0-9]+}}: error: global function 'CImplFunc2' of type '(Double) -> ()' does not match type '(Int32) -> Void' declared by the header{{$}}
 // YES-NOT: cdecl_implementation_features.swift:[[@LINE+1]]:{{[0-9]+}}: error: 'implementation' attribute is only valid when experimental feature CImplementation is enabled
 @implementation @_cdecl("CImplFunc2") func CImplFunc2(_: Double) {}
diff --git a/test/decl/ext/objc_implementation_early_adopter.swift b/test/decl/ext/objc_implementation_early_adopter.swift
@@ -537,14 +537,14 @@ protocol EmptySwiftProto {}
 // @_cdecl for global functions
 //
 
-@_objcImplementation @_cdecl("CImplFunc1")
+@implementation @_cdecl("CImplFunc1")
 func CImplFunc1(_: Int32) {
   // OK
 }
 
-@_objcImplementation(BadCategory) @_cdecl("CImplFunc2")
+@implementation(BadCategory) @_cdecl("CImplFunc2")
 func CImplFunc2(_: Int32) {
-  // expected-error@-2 {{global function 'CImplFunc2' does not belong to an Objective-C category; remove the category name from this attribute}} {{21-34=}}
+  // expected-error@-2 {{global function 'CImplFunc2' does not belong to an Objective-C category; remove the category name from this attribute}} {{16-29=}}
 }
 
 @_objcImplementation @_cdecl("CImplFuncMissing")
@@ -557,12 +557,12 @@ func CImplFuncMismatch1(_: Float) {
   // expected-warning@-1 {{global function 'CImplFuncMismatch1' of type '(Float) -> ()' does not match type '(Int32) -> Void' declared by the header}}
 }
 
-@_objcImplementation @_cdecl("CImplFuncMismatch2")
+@implementation @_cdecl("CImplFuncMismatch2")
 func CImplFuncMismatch2(_: Int32) -> Float {
-  // expected-warning@-1 {{global function 'CImplFuncMismatch2' of type '(Int32) -> Float' does not match type '(Int32) -> Void' declared by the header}}
+  // expected-error@-1 {{global function 'CImplFuncMismatch2' of type '(Int32) -> Float' does not match type '(Int32) -> Void' declared by the header}}
 }
 
-@_objcImplementation @_cdecl("CImplFuncMismatch3")
+@implementation @_cdecl("CImplFuncMismatch3")
 func CImplFuncMismatch3(_: Any?) {
   // OK
 }
@@ -572,18 +572,18 @@ func CImplFuncMismatch4(_: Any) {
   // expected-warning@-1 {{global function 'CImplFuncMismatch4' of type '(Any) -> ()' does not match type '(Any?) -> Void' declared by the header}}
 }
 
-@_objcImplementation @_cdecl("CImplFuncMismatch5")
+@implementation @_cdecl("CImplFuncMismatch5")
 func CImplFuncMismatch5(_: Any) {
   // OK
 }
 
-@_objcImplementation @_cdecl("CImplFuncMismatch6")
+@implementation @_cdecl("CImplFuncMismatch6")
 func CImplFuncMismatch6(_: Any!) {
   // OK, mismatch allowed
 }
 
 
-@_objcImplementation @_cdecl("CImplFuncMismatch3a")
+@implementation @_cdecl("CImplFuncMismatch3a")
 func CImplFuncMismatch3a(_: Int32) -> Any? {
   // OK
 }
@@ -593,23 +593,23 @@ func CImplFuncMismatch4a(_: Int32) -> Any {
   // expected-warning@-1 {{global function 'CImplFuncMismatch4a' of type '(Int32) -> Any' does not match type '(Int32) -> Any?' declared by the header}}
 }
 
-@_objcImplementation @_cdecl("CImplFuncMismatch5a")
+@implementation @_cdecl("CImplFuncMismatch5a")
 func CImplFuncMismatch5a(_: Int32) -> Any {
   // OK
 }
 
-@_objcImplementation @_cdecl("CImplFuncMismatch6a")
+@implementation @_cdecl("CImplFuncMismatch6a")
 func CImplFuncMismatch6a(_: Int32) -> Any! {
   // OK, mismatch allowed
 }
 
-@_objcImplementation @_cdecl("CImplFuncNameMismatch1")
+@implementation @_cdecl("CImplFuncNameMismatch1")
 func mismatchedName1(_: Int32) {
   // expected-error@-2 {{could not find imported function 'CImplFuncNameMismatch1' matching global function 'mismatchedName1'; make sure you import the module or header that declares it}}
   // FIXME: Improve diagnostic for a partial match.
 }
 
-@_objcImplementation @_cdecl("mismatchedName2")
+@implementation @_cdecl("mismatchedName2")
 func CImplFuncNameMismatch2(_: Int32) {
   // expected-error@-2 {{could not find imported function 'mismatchedName2' matching global function 'CImplFuncNameMismatch2'; make sure you import the module or header that declares it}}
   // FIXME: Improve diagnostic for a partial match.
@@ -619,14 +619,14 @@ func CImplFuncNameMismatch2(_: Int32) {
 // TODO: @_cdecl for global functions imported as computed vars
 //
 var cImplComputedGlobal1: Int32 {
-  @_objcImplementation @_cdecl("CImplGetComputedGlobal1")
+  @implementation @_cdecl("CImplGetComputedGlobal1")
   get {
     // FIXME: Lookup for vars isn't working yet
     // expected-error@-3 {{could not find imported function 'CImplGetComputedGlobal1' matching getter for var 'cImplComputedGlobal1'; make sure you import the module or header that declares it}}
     return 0
   }
 
-  @_objcImplementation @_cdecl("CImplSetComputedGlobal1")
+  @implementation @_cdecl("CImplSetComputedGlobal1")
   set {
     // FIXME: Lookup for vars isn't working yet
     // expected-error@-3 {{could not find imported function 'CImplSetComputedGlobal1' matching setter for var 'cImplComputedGlobal1'; make sure you import the module or header that declares it}}
@@ -638,7 +638,7 @@ var cImplComputedGlobal1: Int32 {
 // TODO: @_cdecl for import-as-member functions
 //
 extension CImplStruct {
-  @_objcImplementation @_cdecl("CImplStructStaticFunc1")
+  @implementation @_cdecl("CImplStructStaticFunc1")
   static func staticFunc1(_: Int32) {
     // FIXME: Add underlying support for this
     // expected-error@-3 {{@_cdecl can only be applied to global functions}}
