Do not merge

include/swift/AST/DiagnosticsSema.def

@@ -2900,17 +2900,14 @@ ERROR(decl_from_hidden_module,none,
       "in an extension with conditional conformances}2; "
       "%select{%3 has been imported as implementation-only|"
       "it is an SPI imported from %3|"
-      "it is SPI|"
-      "%3 was not imported by this file}4",
+      "it is SPI}4",
       (DescriptiveDeclKind, DeclName, unsigned, Identifier, unsigned))
 WARNING(decl_from_hidden_module_warn,none,
-      "cannot use %0 %1 %select{here|as property wrapper here|"
-      "as result builder here|"
+      "cannot use %0 %1 %select{in SPI|as property wrapper in SPI|"
+      "as result builder in SPI|"
       "in an extension with public or '@usableFromInline' members|"
       "in an extension with conditional conformances}2; "
-      "%select{%3 has been imported as implementation-only|"
-      "<<ERROR>>|<<ERROR>>|"
-      "%3 was not imported by this file}4",
+      "%select{%3 has been imported as implementation-only}4",
       (DescriptiveDeclKind, DeclName, unsigned, Identifier, unsigned))
 ERROR(conformance_from_implementation_only_module,none,
       "cannot use conformance of %0 to %1 %select{here|as property wrapper here|"
@@ -5785,15 +5782,7 @@ ERROR(inlinable_decl_ref_from_hidden_module,
       none, "%0 %1 cannot be used in " FRAGILE_FUNC_KIND "2 "
       "because %select{%3 was imported implementation-only|"
       "it is an SPI imported from %3|"
-      "it is SPI|"
-      "%3 was not imported by this file}4",
-      (DescriptiveDeclKind, DeclName, unsigned, Identifier, unsigned))
-
-WARNING(inlinable_decl_ref_from_hidden_module_warn,
-      none, "%0 %1 cannot be used in " FRAGILE_FUNC_KIND "2 "
-      "because %select{<<ERROR>>|<<ERROR>>|<<ERROR>>|"
-      "%3 was not imported by this file}4"
-      "; this is an error in Swift 6",
+      "it is SPI}4",
       (DescriptiveDeclKind, DeclName, unsigned, Identifier, unsigned))
 
 ERROR(availability_macro_in_inlinable, none,

include/swift/AST/SourceFile.h

@@ -31,7 +31,6 @@ class PersistentParserState;
 /// \sa getRestrictedImportKind
 enum class RestrictedImportKind {
   ImplementationOnly,
-  Implicit,
   None // No restriction, i.e. the module is imported publicly.
 };
 

lib/AST/Module.cpp

@@ -2442,18 +2442,14 @@ bool SourceFile::hasTestableOrPrivateImport(
 
 RestrictedImportKind SourceFile::getRestrictedImportKind(const ModuleDecl *module) const {
   auto &imports = getASTContext().getImportCache();
-  RestrictedImportKind importKind = RestrictedImportKind::Implicit;
 
   // Look at the imports of this source file.
   for (auto &desc : *Imports) {
     // Ignore implementation-only imports.
-    if (desc.options.contains(ImportFlags::ImplementationOnly)) {
-      if (imports.isImportedBy(module, desc.module.importedModule))
-        importKind = RestrictedImportKind::ImplementationOnly;
+    if (desc.options.contains(ImportFlags::ImplementationOnly))
       continue;
-    }
 
-    // If the module is imported publicly, it's not imported
+    // If the module is imported this way, it's not imported
     // implementation-only.
     if (imports.isImportedBy(module, desc.module.importedModule))
       return RestrictedImportKind::None;
@@ -2463,7 +2459,7 @@ RestrictedImportKind SourceFile::getRestrictedImportKind(const ModuleDecl *modul
   if (imports.isImportedBy(module, getParentModule()))
     return RestrictedImportKind::None;
 
-  return importKind;
+  return RestrictedImportKind::ImplementationOnly;
 }
 
 bool ModuleDecl::isImportedImplementationOnly(const ModuleDecl *module) const {

lib/Sema/ResilienceDiagnostics.cpp

@@ -146,16 +146,7 @@ TypeChecker::diagnoseDeclRefExportability(SourceLoc loc,
 
     D->diagnose(diag::kind_declared_here, DescriptiveDeclKind::Type);
   } else {
-    // Only implicitly imported decls should be reported as a warning,
-    // and only for language versions below Swift 6.
-    assert(downgradeToWarning == DowngradeToWarning::No ||
-           originKind == DisallowedOriginKind::ImplicitlyImported &&
-           "Only implicitly imported decls should be reported as a warning.");
-    auto errorOrWarning = downgradeToWarning == DowngradeToWarning::Yes?
-                              diag::inlinable_decl_ref_from_hidden_module_warn:
-                              diag::inlinable_decl_ref_from_hidden_module;
-
-    ctx.Diags.diagnose(loc, errorOrWarning,
+    ctx.Diags.diagnose(loc, diag::inlinable_decl_ref_from_hidden_module,
                        D->getDescriptiveKind(), D->getName(),
                        fragileKind.getSelector(), definingModule->getName(),
                        static_cast<unsigned>(originKind));

lib/Sema/TypeCheckAccess.cpp

@@ -1511,15 +1511,6 @@ swift::getDisallowedOriginKind(const Decl *decl,
     if (where.isSPI())
       downgradeToWarning = DowngradeToWarning::Yes;
 
-    // Before Swift 6, implicit imports were not reported unless an
-    // implementation-only import was also present. Downgrade to a warning
-    // just in this case.
-    if (howImported == RestrictedImportKind::Implicit &&
-        !SF->getASTContext().isSwiftVersionAtLeast(6) &&
-        !SF->hasImplementationOnlyImports()) {
-      downgradeToWarning = DowngradeToWarning::Yes;
-    }
-
     // Even if the current module is @_implementationOnly, Swift should
     // not report an error in the cases where the decl is also exported from
     // a non @_implementationOnly module. Thus, we check to see if there is
@@ -1540,12 +1531,9 @@ swift::getDisallowedOriginKind(const Decl *decl,
             continue;
           }
         }
-        auto owningModule = redecl->getOwningModule();
-        if (!owningModule)
-          continue;
         auto moduleWrapper =
             decl->getASTContext().getClangModuleLoader()->getWrapperForModule(
-                owningModule);
+                redecl->getOwningModule());
         auto visibleAccessPath =
             find_if(sfImportedModules, [&moduleWrapper](auto importedModule) {
               return importedModule.importedModule == moduleWrapper ||
@@ -1557,10 +1545,7 @@ swift::getDisallowedOriginKind(const Decl *decl,
         }
       }
     }
-
-    // Restrictively imported, cannot be reexported.
-    if (howImported == RestrictedImportKind::Implicit)
-      return DisallowedOriginKind::ImplicitlyImported;
+    // Implementation-only imported, cannot be reexported.
     return DisallowedOriginKind::ImplementationOnly;
   } else if ((decl->isSPI() || decl->isAvailableAsSPI()) && !where.isSPI()) {
     if (decl->isAvailableAsSPI() && !decl->isSPI()) {

lib/Sema/TypeCheckAccess.h

@@ -35,14 +35,12 @@ void checkAccessControl(Decl *D);
 // Problematic origin of an exported type.
 //
 // This enum must be kept in sync with
-// diag::inlinable_decl_ref_from_hidden_module,
 // diag::decl_from_hidden_module and
 // diag::conformance_from_implementation_only_module.
 enum class DisallowedOriginKind : uint8_t {
   ImplementationOnly,
   SPIImported,
   SPILocal,
-  ImplicitlyImported,
   None
 };
 

stdlib/public/Cxx/std/std.swift

@@ -12,3 +12,5 @@
 
 @_exported import std // Clang module
 @_exported import Cxx // Swift module
+
+public var dummy: Int = 1

test/SPI/implementation_only_spi_import_exposability.swift

@@ -26,8 +26,8 @@ public protocol IOIProtocol {}
 
 @_spi(A) @_implementationOnly import Lib
 
-@_spi(B) public func leakSPIStruct(_ a: SPIStruct) -> SPIStruct { fatalError() } // expected-warning 2 {{cannot use struct 'SPIStruct' here; 'Lib' has been imported as implementation-only}}
-@_spi(B) public func leakIOIStruct(_ a: IOIStruct) -> IOIStruct { fatalError() } // expected-warning 2 {{cannot use struct 'IOIStruct' here; 'Lib' has been imported as implementation-only}}
+@_spi(B) public func leakSPIStruct(_ a: SPIStruct) -> SPIStruct { fatalError() } // expected-warning 2 {{cannot use struct 'SPIStruct' in SPI; 'Lib' has been imported as implementation-only}}
+@_spi(B) public func leakIOIStruct(_ a: IOIStruct) -> IOIStruct { fatalError() } // expected-warning 2 {{cannot use struct 'IOIStruct' in SPI; 'Lib' has been imported as implementation-only}}
 
 public struct PublicStruct : IOIProtocol, SPIProtocol { // expected-error {{cannot use protocol 'IOIProtocol' here; 'Lib' has been imported as implementation-only}}
 // expected-error @-1 {{cannot use protocol 'SPIProtocol' here; 'Lib' has been imported as implementation-only}}
@@ -46,8 +46,8 @@ public struct PublicStruct : IOIProtocol, SPIProtocol { // expected-error {{cann
 }
 
 @_spi(B)
-public struct LocalSPIStruct : IOIProtocol, SPIProtocol { // expected-warning {{cannot use protocol 'IOIProtocol' here; 'Lib' has been imported as implementation-only}}
-// expected-warning @-1 {{cannot use protocol 'SPIProtocol' here; 'Lib' has been imported as implementation-only}}
+public struct LocalSPIStruct : IOIProtocol, SPIProtocol { // expected-warning {{cannot use protocol 'IOIProtocol' in SPI; 'Lib' has been imported as implementation-only}}
+// expected-warning @-1 {{cannot use protocol 'SPIProtocol' in SPI; 'Lib' has been imported as implementation-only}}
 }
 
 #endif