[cxx-interop] Avoid linker errors for multiple instantiations of a templated struct with non-type parameters

When mangling the name of a C++ template specialization, we currently ignore non-type templated parameter. This causes two different instantiations of the same templated type to have the same mangled name, triggering linker errors.

This change makes sure we mangle all of the templated parameters by relying on Clang mangling logic.

rdar://107757051

Author: egorzhdan

lib/AST/ASTMangler.cpp

@@ -2647,11 +2647,34 @@ void ASTMangler::appendAnyGenericType(const GenericTypeDecl *decl) {
       appendIdentifier(protocol->getObjCRuntimeNameAsString());
     } else if (auto ctsd = dyn_cast<clang::ClassTemplateSpecializationDecl>(namedDecl)) {
       // If this is a `ClassTemplateSpecializationDecl`, it was
-      // imported as a Swift decl with `__CxxTemplateInst...` name.
-      // `ClassTemplateSpecializationDecl`'s name does not include information about
-      // template arguments, and in order to prevent name clashes we use the
-      // name of the Swift decl which does include template arguments.
-      appendIdentifier(nominal->getName().str());
+      // imported as a Swift decl with `X<...>` name. Some types will be
+      // imported as X<_>, for instance, if they have non-type templated
+      // parameters. To disambiguate different specializations of the same
+      // templated type, we use a different mangling mechanism for C++ template
+      // specializations.
+      auto &clangCtx = ctsd->getASTContext();
+      // Itanium mangler produces valid Swift identifiers, use it to generate a
+      // name for this instantiation.
+      std::unique_ptr<clang::MangleContext> clangMangler{
+          clang::ItaniumMangleContext::create(clangCtx,
+                                              clangCtx.getDiagnostics())};
+
+      llvm::SmallString<128> storage;
+      llvm::raw_svector_ostream buffer(storage);
+      clangMangler->mangleTypeName(clangCtx.getRecordType(ctsd), buffer);
+      // The Itanium mangler does not provide a way to get the mangled
+      // representation of a type. Instead, we call mangleTypeName() that
+      // returns the name of the RTTI typeinfo symbol, and remove the _ZTS
+      // prefix. Then we prepend __CxxTemplateInst to reduce chances of conflict
+      // with regular C and C++ structs.
+      llvm::SmallString<128> mangledNameStorage;
+      llvm::raw_svector_ostream mangledName(mangledNameStorage);
+      assert(buffer.str().take_front(4) == "_ZTS");
+      mangledName << CXX_TEMPLATE_INST_PREFIX << buffer.str().drop_front(4);
+
+      StringRef mangledId =
+          decl->getASTContext().AllocateCopy(mangledName.str());
+      appendIdentifier(mangledId.str());
     } else {
       appendIdentifier(namedDecl->getName());
     }

test/Interop/Cxx/namespace/class-inline-namespace-irgen.swift

@@ -48,7 +48,7 @@ extension Parent.TypedefInInlineChild {
     return ""
   }
 }
-// CHECK: define hidden swiftcc {{.*}} @"$sSo6ParentO11InlineChildO0033TemplateInInlineChildInt8_ehGIixbV4testE6stringSSvg"()
+// CHECK: define hidden swiftcc {{.*}} @"$sSo6ParentO11InlineChildO027__CxxTemplateInstN6Parent11b7Child21e2InbC4IcEEV4testE6stringSSvg"()
 
 extension Parent.InInlineChild {
   func doSomething() {
@@ -70,22 +70,22 @@ extension Parent.InlineChild.InSecondInlineChild {
 }
 // define hidden swiftcc {{.*}} @"$sSo6ParentO11InlineChildO06SecondbC0O02IndbC0V4testE1ySivg"()
 
-// CHECK: define hidden swiftcc {{.*}} @"$s4test3useySSSo6ParentO11InlineChildO0033TemplateInInlineChildInt8_ehGIixbVF"()
-// CHECK: call swiftcc {{.*}} @"$sSo6ParentO11InlineChildO0033TemplateInInlineChildInt8_ehGIixbV4testE6stringSSvg"
+// CHECK: define hidden swiftcc {{.*}} @"$s4test3useySSSo6ParentO11InlineChildO027__CxxTemplateInstN6Parent11d7Child21g2IndE4IcEEVF"()
+// CHECK: call swiftcc {{.*}} @"$sSo6ParentO11InlineChildO027__CxxTemplateInstN6Parent11b7Child21e2InbC4IcEEV4testE6stringSSvg"
 func use(_ x: Parent.TypedefInInlineChild) -> String {
   let s = x.string
   return s
 }
 
-// CHECK: define hidden swiftcc {{.*}} @"$s4test4use2ySSSo6ParentO11InlineChildO0033TemplateInInlineChildInt8_ehGIixbVF"()
-// CHECK: call swiftcc {{.*}} @"$sSo6ParentO11InlineChildO0033TemplateInInlineChildInt8_ehGIixbV4testE6stringSSvg"
+// CHECK: define hidden swiftcc {{.*}} @"$s4test4use2ySSSo6ParentO11InlineChildO027__CxxTemplateInstN6Parent11d7Child21g2IndE4IcEEVF"()
+// CHECK: call swiftcc {{.*}} @"$sSo6ParentO11InlineChildO027__CxxTemplateInstN6Parent11b7Child21e2InbC4IcEEV4testE6stringSSvg"
 func use2(_ x: Parent.InlineChild.TypedefInInlineChild) -> String {
   let s = x.string
   return s
 }
 
 // define swiftcc void @"$s4testAAyySo6ParentO11InlineChildO02IncD0VF"()
-// CHECK: alloca %TSo6ParentO11InlineChildO0033TemplateInInlineChildInt8_ehGIixbV
+// CHECK: alloca %TSo6ParentO11InlineChildO027__CxxTemplateInstN6Parent11b7Child21e2InbC4IcEEV
 // CHECK: call {{.*}} @{{_ZN6Parent11InlineChild21TemplateInInlineChildIcEC|"\?\?0\?\$TemplateInInlineChild@D@InlineChild@Parent@@QEAA@XZ"}}
 // CHECK: call swiftcc void @"$sSo6ParentO11InlineChildO02InbC0V4testE11doSomethingyyF"(
 // CHECK: call swiftcc {{.*}} @"$sSo6ParentO11InlineChildO06SecondbC0O02IndbC0V4testE1xSivg"(

test/Interop/Cxx/templates/Inputs/class-template-non-type-parameter.h

@@ -8,5 +8,6 @@ using size_t = __SIZE_TYPE__;
 template <class T, size_t Size> struct MagicArray { T t[Size]; };
 
 typedef MagicArray<int, 2> MagicIntPair;
+typedef MagicArray<int, 3> MagicIntTriple;
 
 #endif // TEST_INTEROP_CXX_TEMPLATES_INPUTS_CLASS_TEMPLATE_NON_TYPE_PARAMETER_H

test/Interop/Cxx/templates/class-template-instantiation-demangling.swift

@@ -9,5 +9,5 @@ public func returnInstantiation() -> WrappedMagicInt {
   return WrappedMagicInt()
 }
 
-// CHECK: $s4main20receiveInstantiationyySo0025MagicWrapperInt32_lsFCfibVzF(%TSo0025MagicWrapperInt32_lsFCfibV* ---> @$s4main20receiveInstantiationyySo0025MagicWrapperInt32_lsFCfibVzF(%TSo0025MagicWrapperInt32_lsFCfibV*
-// CHECK: $s4main19returnInstantiationSo0025MagicWrapperInt32_lsFCfibVyF() ---> @$s4main19returnInstantiationSo0025MagicWrapperInt32_lsFCfibVyF()
+// CHECK: $s4main20receiveInstantiationyySo34__CxxTemplateInst12MagicWrapperIiEVzF ---> main.receiveInstantiation(inout __C.__CxxTemplateInst12MagicWrapperIiE) -> ()
+// CHECK: $s4main19returnInstantiationSo34__CxxTemplateInst12MagicWrapperIiEVyF ---> main.returnInstantiation() -> __C.__CxxTemplateInst12MagicWrapperIiE

test/Interop/Cxx/templates/class-template-non-type-parameter-irgen.swift

@@ -0,0 +1,9 @@
+// RUN: %target-swift-emit-ir %s -I %S/Inputs -enable-experimental-cxx-interop | %FileCheck %s
+
+import ClassTemplateNonTypeParameter
+
+let p = MagicIntPair()
+let t = MagicIntTriple()
+
+// CHECK: @"$s4main1pSo36__CxxTemplateInst10MagicArrayIiLm2EEVvp"
+// CHECK: @"$s4main1tSo36__CxxTemplateInst10MagicArrayIiLm3EEVvp"

test/Interop/Cxx/templates/class-template-non-type-parameter.swift

@@ -10,6 +10,9 @@ var TemplatesTestSuite = TestSuite("TemplatesTestSuite")
 TemplatesTestSuite.test("typedeffed-non-type-parameter") {
   let pair = MagicIntPair(t: (1, 2))
   expectEqual(pair.t, (1, 2))
+
+  let triple = MagicIntTriple(t: (1, 2, 3))
+  expectEqual(triple.t, (1, 2, 3))
 }
 
 // TODO: This test doesn't work because Swift doesn't support defaulted generic

test/Interop/Cxx/templates/linkage-of-swift-symbols-for-imported-types-irgen.swift

@@ -16,13 +16,13 @@ public func getMagicNumberForLinkageComparison() -> Any {
 // CHECK: $sSo11MagicNumberVMf" = linkonce_odr hidden constant
 // CHECK: $sSo11MagicNumberVML" = linkonce_odr hidden global
 
-// CHECK: $sSo0031MagicWrapperMagicNumber_IJFJhAbVWV" = linkonce_odr hidden constant
-// CHECK: $sSo0031MagicWrapperMagicNumber_IJFJhAbVMn" = linkonce_odr hidden constant
-// CHECK: $sSo0031MagicWrapperMagicNumber_IJFJhAbVMf" = linkonce_odr hidden constant
-// CHECK: $sSo0031MagicWrapperMagicNumber_IJFJhAbVML" = linkonce_odr hidden global
+// CHECK: $sSo034__CxxTemplateInst12MagicWrapperI11D7NumberEVWV" = linkonce_odr hidden constant
+// CHECK: $sSo034__CxxTemplateInst12MagicWrapperI11D7NumberEVMn" = linkonce_odr hidden constant
+// CHECK: $sSo034__CxxTemplateInst12MagicWrapperI11D7NumberEVMf" = linkonce_odr hidden constant
+// CHECK: $sSo034__CxxTemplateInst12MagicWrapperI11D7NumberEVML" = linkonce_odr hidden global
 
 // CHECK: $sSo11MagicNumberVMB" = linkonce_odr hidden constant
 // CHECK: $sSo11MagicNumberVMF" = linkonce_odr hidden constant
 
-// CHECK: $sSo0031MagicWrapperMagicNumber_IJFJhAbVMB" = linkonce_odr hidden constant
-// CHECK: $sSo0031MagicWrapperMagicNumber_IJFJhAbVMF" = linkonce_odr hidden constant
+// CHECK: $sSo034__CxxTemplateInst12MagicWrapperI11D7NumberEVMB" = linkonce_odr hidden constant
+// CHECK: $sSo034__CxxTemplateInst12MagicWrapperI11D7NumberEVMF" = linkonce_odr hidden constant

test/Interop/Cxx/templates/mangling-irgen.swift

@@ -6,16 +6,16 @@ import Mangling
 public func receiveInstantiation(_ i: inout WrappedMagicInt) {}
 
 // Don't forget to update manglings.txt when changing s4main20receiveInstantiationyySo34__CxxTemplateInst12MagicWrapperIiEVzF
-// CHECK: define {{(protected |dllexport )?}}swiftcc void @"$s4main20receiveInstantiationyySo0025MagicWrapperInt32_lsFCfibVzF"(%TSo0025MagicWrapperInt32_lsFCfibV* nocapture dereferenceable(1) %0)
+// CHECK: define {{(protected |dllexport )?}}swiftcc void @"$s4main20receiveInstantiationyySo34__CxxTemplateInst12MagicWrapperIiEVzF"(%TSo34__CxxTemplateInst12MagicWrapperIiEV* nocapture dereferenceable(1) %0)
 
 public func receiveInstantiation(_ i: inout WrappedMagicBool) {}
 
-// CHECK: define {{(protected |dllexport )?}}swiftcc void @"$s4main20receiveInstantiationyySo0024MagicWrapperBool_npAIefbVzF"(%TSo0024MagicWrapperBool_npAIefbV* nocapture dereferenceable(1) %0)
+// CHECK: define {{(protected |dllexport )?}}swiftcc void @"$s4main20receiveInstantiationyySo34__CxxTemplateInst12MagicWrapperIbEVzF"(%TSo34__CxxTemplateInst12MagicWrapperIbEV* nocapture dereferenceable(1) %0)
 
 public func returnInstantiation() -> WrappedMagicInt {
   return WrappedMagicInt()
 }
 
 // Don't forget to update manglings.txt when changing s4main19returnInstantiationSo34__CxxTemplateInst12MagicWrapperIiEVyF
-// CHECK: define {{(protected |dllexport )?}}swiftcc void @"$s4main19returnInstantiationSo0025MagicWrapperInt32_lsFCfibVyF"()
+// CHECK: define {{(protected |dllexport )?}}swiftcc void @"$s4main19returnInstantiationSo34__CxxTemplateInst12MagicWrapperIiEVyF"()
 

test/Interop/Cxx/templates/mangling-silgen.swift

@@ -5,16 +5,16 @@ import Mangling
 public func recvInstantiation(_ i: inout WrappedMagicInt) {}
 
 // CHECK: // recvInstantiation(_:)
-// CHECK: sil @$s4main17recvInstantiationyySo0025MagicWrapperInt32_lsFCfibVzF : $@convention(thin) (@inout MagicWrapper<Int32>) -> ()
+// CHECK: sil @$s4main17recvInstantiationyySo34__CxxTemplateInst12MagicWrapperIiEVzF : $@convention(thin) (@inout __CxxTemplateInst12MagicWrapperIiE) -> ()
 
 public func recvInstantiation(_ i: inout WrappedMagicBool) {}
 
 // CHECK: // recvInstantiation(_:)
-// CHECK: sil @$s4main17recvInstantiationyySo0024MagicWrapperBool_npAIefbVzF : $@convention(thin) (@inout MagicWrapper<Bool>) -> ()
+// CHECK: sil @$s4main17recvInstantiationyySo34__CxxTemplateInst12MagicWrapperIbEVzF : $@convention(thin) (@inout __CxxTemplateInst12MagicWrapperIbE) -> ()
 
 public func returnInstantiation() -> WrappedMagicInt {
   return WrappedMagicInt()
 }
 
 // CHECK: // returnInstantiation()
-// CHECK: sil @$s4main19returnInstantiationSo0025MagicWrapperInt32_lsFCfibVyF : $@convention(thin) () -> MagicWrapper<Int32>
+// CHECK: sil @$s4main19returnInstantiationSo34__CxxTemplateInst12MagicWrapperIiEVyF : $@convention(thin) () -> __CxxTemplateInst12MagicWrapperIiE

test/Interop/CxxToSwiftToCxx/bridge-cxx-struct-back-to-cxx.swift

@@ -156,15 +156,15 @@ public func takeTrivialInout(_ x: inout Trivial) {
 // CHECK-NEXT: #endif
 
 
-// CHECK: SWIFT_EXTERN void $s8UseCxxTy13retNonTrivialSo2nsO0031NonTrivialTemplateInt32_fbGJhubVyF(SWIFT_INDIRECT_RESULT void * _Nonnull) SWIFT_NOEXCEPT SWIFT_CALL; // retNonTrivial()
+// CHECK: SWIFT_EXTERN void $s8UseCxxTy13retNonTrivialSo2nsO02__b18TemplateInstN2ns18efH4IiEEVyF(SWIFT_INDIRECT_RESULT void * _Nonnull) SWIFT_NOEXCEPT SWIFT_CALL; // retNonTrivial()
 // CHECK: SWIFT_EXTERN struct swift_interop_returnStub_UseCxxTy_uint32_t_0_4 $s8UseCxxTy10retTrivialSo0E0VyF(void) SWIFT_NOEXCEPT SWIFT_CALL; // retTrivial()
 
 // CHECK: ns::Immortal *_Nonnull retImmortal() noexcept SWIFT_SYMBOL({{.*}}) SWIFT_WARN_UNUSED_RESULT {
 // CHECK-NEXT: return _impl::$s8UseCxxTy11retImmortalSo2nsO0E0VyF();
 // CHECK-NEXT: }
 
 // CHECK:  ns::ImmortalTemplate<int> *_Nonnull retImmortalTemplate() noexcept SWIFT_SYMBOL({{.*}}) SWIFT_WARN_UNUSED_RESULT {
-// CHECK-NEXT: return _impl::$s8UseCxxTy19retImmortalTemplateSo2nsO0029ImmortalTemplateInt32_hEFAhqbVyF();
+// CHECK-NEXT: return _impl::$s8UseCxxTy19retImmortalTemplateSo2nsO02__bf10InstN2ns16eF4IiEEVyF();
 // CHECK-NEXT: }
 
 // CHECK: } // end namespace
@@ -173,7 +173,7 @@ public func takeTrivialInout(_ x: inout Trivial) {
 // CHECK-NEXT: namespace _impl {
 // CHECK-EMPTY:
 // CHECK-NEXT: // Type metadata accessor for NonTrivialTemplateInt
-// CHECK-NEXT: SWIFT_EXTERN swift::_impl::MetadataResponseTy $sSo2nsO0031NonTrivialTemplateInt32_fbGJhubVMa(swift::_impl::MetadataRequestTy) SWIFT_NOEXCEPT SWIFT_CALL;
+// CHECK-NEXT: SWIFT_EXTERN swift::_impl::MetadataResponseTy $sSo2nsO033__CxxTemplateInstN2ns18NonTrivialC4IiEEVMa(swift::_impl::MetadataRequestTy) SWIFT_NOEXCEPT SWIFT_CALL;
 // CHECK-EMPTY:
 // CHECK-EMPTY:
 // CHECK-NEXT: } // namespace _impl
@@ -185,7 +185,7 @@ public func takeTrivialInout(_ x: inout Trivial) {
 // CHECK-NEXT: template<>
 // CHECK-NEXT: struct TypeMetadataTrait<ns::NonTrivialTemplateInt> {
 // CHECK-NEXT:   static SWIFT_INLINE_THUNK void * _Nonnull getTypeMetadata() {
-// CHECK-NEXT:     return _impl::$sSo2nsO0031NonTrivialTemplateInt32_fbGJhubVMa(0)._0;
+// CHECK-NEXT:     return _impl::$sSo2nsO033__CxxTemplateInstN2ns18NonTrivialC4IiEEVMa(0)._0;
 // CHECK-NEXT:   }
 // CHECK-NEXT: };
 // CHECK-NEXT: namespace _impl{
@@ -200,7 +200,7 @@ public func takeTrivialInout(_ x: inout Trivial) {
 // CHECK: SWIFT_INLINE_THUNK ns::NonTrivialTemplate<int> retNonTrivial() noexcept SWIFT_SYMBOL({{.*}}) SWIFT_WARN_UNUSED_RESULT {
 // CHECK-NEXT: alignas(alignof(ns::NonTrivialTemplate<int>)) char storage[sizeof(ns::NonTrivialTemplate<int>)];
 // CHECK-NEXT: auto * _Nonnull storageObjectPtr = reinterpret_cast<ns::NonTrivialTemplate<int> *>(storage);
-// CHECK-NEXT: _impl::$s8UseCxxTy13retNonTrivialSo2nsO0031NonTrivialTemplateInt32_fbGJhubVyF(storage);
+// CHECK-NEXT: _impl::$s8UseCxxTy13retNonTrivialSo2nsO02__b18TemplateInstN2ns18efH4IiEEVyF(storage);
 // CHECK-NEXT: ns::NonTrivialTemplate<int> result(static_cast<ns::NonTrivialTemplate<int> &&>(*storageObjectPtr));
 // CHECK-NEXT: storageObjectPtr->~NonTrivialTemplate();
 // CHECK-NEXT: return result;
@@ -212,7 +212,7 @@ public func takeTrivialInout(_ x: inout Trivial) {
 // CHECK-NEXT: namespace _impl {
 // CHECK-EMPTY:
 // CHECK-NEXT: // Type metadata accessor for NonTrivialTemplateTrivial
-// CHECK-NEXT: SWIFT_EXTERN swift::_impl::MetadataResponseTy $sSo2nsO0037NonTrivialTemplateTrivialinNS_CsGGkdcVMa(swift::_impl::MetadataRequestTy) SWIFT_NOEXCEPT SWIFT_CALL;
+// CHECK-NEXT: SWIFT_EXTERN swift::_impl::MetadataResponseTy $sSo2nsO033__CxxTemplateInstN2ns18NonTrivialC20INS_11TrivialinNSEEEVMa(swift::_impl::MetadataRequestTy) SWIFT_NOEXCEPT SWIFT_CALL;
 // CHECK-EMPTY:
 // CHECK-EMPTY:
 // CHECK-NEXT: } // namespace _impl
@@ -224,7 +224,7 @@ public func takeTrivialInout(_ x: inout Trivial) {
 // CHECK-NEXT: template<>
 // CHECK-NEXT: struct TypeMetadataTrait<ns::NonTrivialTemplateTrivial> {
 // CHECK-NEXT:   static SWIFT_INLINE_THUNK void * _Nonnull getTypeMetadata() {
-// CHECK-NEXT:     return _impl::$sSo2nsO0037NonTrivialTemplateTrivialinNS_CsGGkdcVMa(0)._0;
+// CHECK-NEXT:     return _impl::$sSo2nsO033__CxxTemplateInstN2ns18NonTrivialC20INS_11TrivialinNSEEEVMa(0)._0;
 // CHECK-NEXT:   }
 // CHECK-NEXT: };
 // CHECK-NEXT: namespace _impl{
@@ -239,7 +239,7 @@ public func takeTrivialInout(_ x: inout Trivial) {
 // CHECK-NEXT: SWIFT_INLINE_THUNK ns::NonTrivialTemplate<ns::TrivialinNS> retNonTrivial2() noexcept SWIFT_SYMBOL({{.*}}) SWIFT_WARN_UNUSED_RESULT {
 // CHECK-NEXT: alignas(alignof(ns::NonTrivialTemplate<ns::TrivialinNS>)) char storage[sizeof(ns::NonTrivialTemplate<ns::TrivialinNS>)];
 // CHECK-NEXT: auto * _Nonnull storageObjectPtr = reinterpret_cast<ns::NonTrivialTemplate<ns::TrivialinNS> *>(storage);
-// CHECK-NEXT: _impl::$s8UseCxxTy14retNonTrivial2So2nsO0037NonTrivialTemplateTrivialinNS_CsGGkdcVyF(storage);
+// CHECK-NEXT: _impl::$s8UseCxxTy14retNonTrivial2So2nsO02__b18TemplateInstN2ns18e7TrivialH20INS_11TrivialinNSEEEVyF(storage);
 // CHECK-NEXT: ns::NonTrivialTemplate<ns::TrivialinNS> result(static_cast<ns::NonTrivialTemplate<ns::TrivialinNS> &&>(*storageObjectPtr));
 // CHECK-NEXT: storageObjectPtr->~NonTrivialTemplate();
 // CHECK-NEXT: return result;
@@ -268,11 +268,11 @@ public func takeTrivialInout(_ x: inout Trivial) {
 // CHECK-NEXT: }
 
 // CHECK: void takeImmortalTemplate(ns::ImmortalTemplate<int> *_Nonnull x) noexcept SWIFT_SYMBOL({{.*}}) {
-// CHECK-NEXT:   return _impl::$s8UseCxxTy20takeImmortalTemplateyySo2nsO0029ImmortalTemplateInt32_hEFAhqbVF(x);
+// CHECK-NEXT:   return _impl::$s8UseCxxTy20takeImmortalTemplateyySo2nsO02__bf10InstN2ns16eF4IiEEVF(x);
 // CHECK-NEXT: }
 
 // CHECK: SWIFT_INLINE_THUNK void takeNonTrivial2(const ns::NonTrivialTemplate<ns::TrivialinNS>& x) noexcept SWIFT_SYMBOL({{.*}}) {
-// CHECK-NEXT:   return _impl::$s8UseCxxTy15takeNonTrivial2yySo2nsO0037NonTrivialTemplateTrivialinNS_CsGGkdcVF(swift::_impl::getOpaquePointer(x));
+// CHECK-NEXT:   return _impl::$s8UseCxxTy15takeNonTrivial2yySo2nsO02__b18TemplateInstN2ns18e7TrivialH20INS_11TrivialinNSEEEVF(swift::_impl::getOpaquePointer(x));
 // CHECK-NEXT: }
 
 // CHECK: SWIFT_INLINE_THUNK void takeTrivial(const Trivial& x) noexcept SWIFT_SYMBOL({{.*}}) {