Merge pull request #41604 from compnerd/linkage

IRGen: loosen linkage on vtable stubs for static linking

Author: compnerd

lib/IRGen/GenDecl.cpp

@@ -2025,7 +2025,9 @@ void IRGenModule::emitVTableStubs() {
       alias->setVisibility(llvm::GlobalValue::HiddenVisibility);
     else
       ApplyIRLinkage(IRGen.Opts.InternalizeSymbols
-                        ? IRLinkage::Internal
+                        ? IRLinkage{llvm::GlobalValue::ExternalLinkage,
+                                    llvm::GlobalValue::HiddenVisibility,
+                                    llvm::GlobalValue::DefaultStorageClass}
                         : IRLinkage::ExternalExport).to(alias);
   }
 }

test/IRGen/static-vtable-stubs.swift

@@ -0,0 +1,21 @@
+// RUN: %empty-directory(%t)
+// RUN: split-file --leading-lines %s %t
+// RUN: %swift-target-frontend -parse-as-library -static -O -module-name M -c -primary-file %t/A.swift %t/B.swift -S -emit-ir -o - | %FileCheck %t/A.swift -check-prefix CHECK
+// RUN: %swift-target-frontend -parse-as-library -static -O -module-name M -c %t/A.swift -primary-file %t/B.swift -S -emit-ir -o - | %FileCheck %t/B.swift -check-prefix CHECK
+
+//--- A.swift
+open class C {
+    private var i: [ObjectIdentifier:Any] = [:]
+}
+
+// CHECK: @"$s1M1CC1i33_807E3D81CC6CDD898084F3279464DDF9LLSDySOypGvg" = hidden alias void (), void ()* @_swift_dead_method_stub
+// CHECK: @"$s1M1CC1i33_807E3D81CC6CDD898084F3279464DDF9LLSDySOypGvs" = hidden alias void (), void ()* @_swift_dead_method_stub
+// CHECK: @"$s1M1CC1i33_807E3D81CC6CDD898084F3279464DDF9LLSDySOypGvM" = hidden alias void (), void ()* @_swift_dead_method_stub
+
+//--- B.swift
+final class D: C {
+}
+
+// CHECK: declare swiftcc %swift.bridge* @"$s1M1CC1i33_807E3D81CC6CDD898084F3279464DDF9LLSDySOypGvg"(%T1M1CC* swiftself) #0
+// CHECK: declare swiftcc void @"$s1M1CC1i33_807E3D81CC6CDD898084F3279464DDF9LLSDySOypGvs"(%swift.bridge*, %T1M1CC* swiftself) #0
+// CHECK: declare swiftcc { i8*, %TSD* } @"$s1M1CC1i33_807E3D81CC6CDD898084F3279464DDF9LLSDySOypGvM"(i8* noalias dereferenceable(32), %T1M1CC* swiftself) #0