[MS ABI] Don't crash while mangling recursive lambdas

We might get into bad situations where we try to embed the signature of
an inner lambda into an outer lambda which cannot work: the inner lambda
wants to embed the name of the outer lambda!

Instead, omit the return type for lambdas.

This fixes PR26105.

N.B.  While we are here, make lambdas nested within functions use an
artificial scope so that they can get demangled.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@258003 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/AST/MicrosoftMangle.cpp b/lib/AST/MicrosoftMangle.cpp
index 4a45f9e4051f1d856318d9118d313fbe09aed57e..0634319cbd1bc7985ddd25d480455ec4ff8636f7 100644 (file)
--- a/lib/AST/MicrosoftMangle.cpp
+++ b/lib/AST/MicrosoftMangle.cpp
@@ -160,14 +160,17 @@ public:
                              raw_ostream &Out) override;
   void mangleStringLiteral(const StringLiteral *SL, raw_ostream &Out) override;
   bool getNextDiscriminator(const NamedDecl *ND, unsigned &disc) {
-    // Lambda closure types are already numbered.
-    if (isLambda(ND))
-      return false;
-
     const DeclContext *DC = getEffectiveDeclContext(ND);
     if (!DC->isFunctionOrMethod())
       return false;
 
+    // Lambda closure types are already numbered, give out a phony number so
+    // that they demangle nicely.
+    if (isLambda(ND)) {
+      disc = 1;
+      return true;
+    }
+
     // Use the canonical number for externally visible decls.
     if (ND->isExternallyVisible()) {
       disc = getASTContext().getManglingNumber(ND);
@@ -1799,9 +1802,12 @@ void MicrosoftCXXNameMangler::mangleFunctionType(const FunctionType *T,
   SourceRange Range;
   if (D) Range = D->getSourceRange();
 
+  bool IsInLambda = false;
   bool IsStructor = false, HasThisQuals = ForceThisQuals, IsCtorClosure = false;
   CallingConv CC = T->getCallConv();
   if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(D)) {
+    if (MD->getParent()->isLambda())
+      IsInLambda = true;
     if (MD->isInstance())
       HasThisQuals = true;
     if (isa<CXXDestructorDecl>(MD)) {
@@ -1875,6 +1881,8 @@ void MicrosoftCXXNameMangler::mangleFunctionType(const FunctionType *T,
              "shouldn't need to mangle __auto_type!");
       mangleSourceName(AT->isDecltypeAuto() ? "<decltype-auto>" : "<auto>");
       Out << '@';
+    } else if (IsInLambda) {
+      Out << '@';
     } else {
       if (ResultType->isVoidType())
         ResultType = ResultType.getUnqualifiedType();

diff --git a/test/CodeGenCXX/exceptions-seh-filter-captures.cpp b/test/CodeGenCXX/exceptions-seh-filter-captures.cpp
index 4e8be72089d5ee5b461bcde47efde71557d8d653..ab75a87698ab05484984f6d07ad32838e56e0434 100644 (file)
--- a/test/CodeGenCXX/exceptions-seh-filter-captures.cpp
+++ b/test/CodeGenCXX/exceptions-seh-filter-captures.cpp
@@ -70,14 +70,14 @@ void test_lambda() {
   lambda();
 }
 
-// CHECK-LABEL: define internal void @"\01??R<lambda_0>@?test_lambda@@YAXXZ@QEBAXXZ"(%class.anon* %this)
+// CHECK-LABEL: define internal void @"\01??R<lambda_0>@?0??test_lambda@@YAXXZ@QEBA@XZ"(%class.anon* %this)
 // CHECK: @llvm.localescape(i32* %[[l2_addr:[^, ]*]])
 // CHECK: store i32 42, i32* %[[l2_addr]], align 4
 // CHECK: invoke void @might_crash()
 
-// CHECK-LABEL: define internal i32 @"\01?filt$0@0@?R<lambda_0>@?test_lambda@@YAXXZ@"(i8* %exception_pointers, i8* %frame_pointer)
-// CHECK: %[[fp:[^ ]*]] = call i8* @llvm.x86.seh.recoverfp(i8* bitcast (void (%class.anon*)* @"\01??R<lambda_0>@?test_lambda@@YAXXZ@QEBAXXZ" to i8*), i8* %frame_pointer)
-// CHECK: %[[l2_i8:[^ ]*]] = call i8* @llvm.localrecover(i8* bitcast (void (%class.anon*)* @"\01??R<lambda_0>@?test_lambda@@YAXXZ@QEBAXXZ" to i8*), i8* %[[fp]], i32 0)
+// CHECK-LABEL: define internal i32 @"\01?filt$0@0@?R<lambda_0>@?0??test_lambda@@YAXXZ@"(i8* %exception_pointers, i8* %frame_pointer)
+// CHECK: %[[fp:[^ ]*]] = call i8* @llvm.x86.seh.recoverfp(i8* bitcast (void (%class.anon*)* @"\01??R<lambda_0>@?0??test_lambda@@YAXXZ@QEBA@XZ" to i8*), i8* %frame_pointer)
+// CHECK: %[[l2_i8:[^ ]*]] = call i8* @llvm.localrecover(i8* bitcast (void (%class.anon*)* @"\01??R<lambda_0>@?0??test_lambda@@YAXXZ@QEBA@XZ" to i8*), i8* %[[fp]], i32 0)
 // CHECK: %[[l2_ptr:[^ ]*]] = bitcast i8* %[[l2_i8]] to i32*
 // CHECK: %[[l2:[^ ]*]] = load i32, i32* %[[l2_ptr]]
 // CHECK: call i32 (i32, ...) @basic_filter(i32 %[[l2]])

diff --git a/test/CodeGenCXX/exceptions-seh.cpp b/test/CodeGenCXX/exceptions-seh.cpp
index abbe95be3404ebafaf712bda39fd113b4ebdac32..589bc2265760472fe57c97503b89a2a3c77916e0 100644 (file)
--- a/test/CodeGenCXX/exceptions-seh.cpp
+++ b/test/CodeGenCXX/exceptions-seh.cpp
@@ -95,7 +95,7 @@ void use_seh_in_lambda() {
 // NOCXX-NOT: invoke
 // NOCXX: ret void
 
-// CHECK-LABEL: define internal void @"\01??R<lambda_0>@?use_seh_in_lambda@@YAXXZ@QEBAXXZ"(%class.anon* %this)
+// CHECK-LABEL: define internal void @"\01??R<lambda_0>@?0??use_seh_in_lambda@@YAXXZ@QEBA@XZ"(%class.anon* %this)
 // CXXEH-SAME:  personality i8* bitcast (i32 (...)* @__C_specific_handler to i8*)
 // CHECK: invoke void @might_throw() #[[NOINLINE]]
 // CHECK: catchpad

diff --git a/test/CodeGenCXX/mangle-ms-cxx11.cpp b/test/CodeGenCXX/mangle-ms-cxx11.cpp
index 999def87fc5eadc3271dce8a9b5f80f95ad95bf8..99384440a1829149858d42411ad58ac13f26d36c 100644 (file)
--- a/test/CodeGenCXX/mangle-ms-cxx11.cpp
+++ b/test/CodeGenCXX/mangle-ms-cxx11.cpp
@@ -166,14 +166,14 @@ inline int define_lambda() {
   static auto lambda = [] { static int local; ++local; return local; };
 // First, we have the static local variable of type "<lambda_1>" inside of
 // "define_lambda".
-// CHECK-DAG: @"\01?lambda@?1??define_lambda@@YAHXZ@4V<lambda_1>@?1@YAHXZ@A"
+// CHECK-DAG: @"\01?lambda@?1??define_lambda@@YAHXZ@4V<lambda_1>@?0??1@YAHXZ@A"
 // Next, we have the "operator()" for "<lambda_1>" which is inside of
 // "define_lambda".
-// CHECK-DAG: @"\01??R<lambda_1>@?define_lambda@@YAHXZ@QBEHXZ"
+// CHECK-DAG: @"\01??R<lambda_1>@?0??define_lambda@@YAHXZ@QBE@XZ"
 // Finally, we have the local which is inside of "<lambda_1>" which is inside of
 // "define_lambda". Hooray.
-// MSVC2013-DAG: @"\01?local@?2???R<lambda_1>@?define_lambda@@YAHXZ@QBEHXZ@4HA"
-// MSVC2015-DAG: @"\01?local@?1???R<lambda_1>@?define_lambda@@YAHXZ@QBEHXZ@4HA"
+// MSVC2013-DAG: @"\01?local@?2???R<lambda_1>@?0??define_lambda@@YAHXZ@QBE@XZ@4HA"
+// MSVC2015-DAG: @"\01?local@?1???R<lambda_1>@?0??define_lambda@@YAHXZ@QBE@XZ@4HA"
   return lambda();
 }
 
@@ -182,12 +182,12 @@ void use_lambda_arg(T) {}
 
 inline void call_with_lambda_arg1() {
   use_lambda_arg([]{});
-  // CHECK-DAG: @"\01??$use_lambda_arg@V<lambda_1>@?call_with_lambda_arg1@@YAXXZ@@@YAXV<lambda_1>@?call_with_lambda_arg1@@YAXXZ@@Z"
+  // CHECK-DAG: @"\01??$use_lambda_arg@V<lambda_1>@?0??call_with_lambda_arg1@@YAXXZ@@@YAXV<lambda_1>@?0??call_with_lambda_arg1@@YAXXZ@@Z"
 }
 
 inline void call_with_lambda_arg2() {
   use_lambda_arg([]{});
-  // CHECK-DAG: @"\01??$use_lambda_arg@V<lambda_1>@?call_with_lambda_arg2@@YAXXZ@@@YAXV<lambda_1>@?call_with_lambda_arg2@@YAXXZ@@Z"
+  // CHECK-DAG: @"\01??$use_lambda_arg@V<lambda_1>@?0??call_with_lambda_arg2@@YAXXZ@@@YAXV<lambda_1>@?0??call_with_lambda_arg2@@YAXXZ@@Z"
 }
 
 int call_lambda() {
@@ -286,3 +286,10 @@ static union {
 };
 // CHECK-DAG: @"\01??$f@T<unnamed-type-$S1>@PR18204@@@PR18204@@YAHPAT<unnamed-type-$S1>@0@@Z"
 }
+
+int PR26105() {
+  auto add = [](int x) { return ([x](int y) { return x + y; }); };
+  return add(3)(4);
+}
+// CHECK-DAG: @"\01??R<lambda_0>@?0??PR26105@@YAHXZ@QBE@H@Z"
+// CHECK-DAG: @"\01??R<lambda_1>@?0???R<lambda_0>@?0??PR26105@@YAHXZ@QBE@H@Z@QBE@H@Z"

diff --git a/test/CodeGenCXX/mangle-ms-cxx14.cpp b/test/CodeGenCXX/mangle-ms-cxx14.cpp
index 9d30c406c8c720dafd4309316c0b578d5c3b7088..084eb7ddf1252bd82c4fc7ed986af5654414ac33 100644 (file)
--- a/test/CodeGenCXX/mangle-ms-cxx14.cpp
+++ b/test/CodeGenCXX/mangle-ms-cxx14.cpp
@@ -35,12 +35,12 @@ auto TemplateFuncionWithLocalLambda(T) {
   return LocalLambdaWithLocalType();
 }
 
-// MSVC2013-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?2???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
-// MSVC2013-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?2???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
-// MSVC2015-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?1???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
-// MSVC2015-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?1???R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
+// MSVC2013-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?2???R<lambda_1>@?0???$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
+// MSVC2013-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?2???R<lambda_1>@?0???$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
+// MSVC2015-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?1???R<lambda_1>@?0???$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
+// MSVC2015-DAG: "\01?ValueFromTemplateFuncionWithLocalLambda@@3ULocalType@?1???R<lambda_1>@?0???$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?3@XZ@A"
 // CHECK-DAG: "\01??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z"
-// CHECK-DAG: "\01??R<lambda_1>@??$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?1@XZ"
+// CHECK-DAG: "\01??R<lambda_1>@?0???$TemplateFuncionWithLocalLambda@H@@YA?A?<auto>@@H@Z@QBE?A?1@XZ"
 auto ValueFromTemplateFuncionWithLocalLambda = TemplateFuncionWithLocalLambda(0);
 
 struct S;

diff --git a/test/CodeGenCXX/pr20719.cpp b/test/CodeGenCXX/pr20719.cpp
index 208d111358471334f6a74ce773afb04a7195203d..1c3b21b0b84e3afa2a916e0a9470ad707620db14 100644 (file)
--- a/test/CodeGenCXX/pr20719.cpp
+++ b/test/CodeGenCXX/pr20719.cpp
@@ -2,8 +2,8 @@
 
 // Make sure that we emit H's constructor twice: once with the first lambda
 // inside of 'lep' and again with the second lambda inside of 'lep'.
-// CHECK-DAG: @"\01??0?$H@V<lambda_1>@??$lep@X@@YAXXZ@@@QAE@XZ"
-// CHECK-DAG: @"\01??0?$H@V<lambda_2>@??$lep@X@@YAXXZ@@@QAE@XZ"
+// CHECK-DAG: @"\01??0?$H@V<lambda_1>@?0???$lep@X@@YAXXZ@@@QAE@XZ"
+// CHECK-DAG: @"\01??0?$H@V<lambda_2>@?0???$lep@X@@YAXXZ@@@QAE@XZ"
 
 template <typename>
 struct H {