[Clang] Fix the mangling of lambdas (#89204)
Lambdas used in the initializer of a local class were not mangling the
name of the member.
Fixes #88906
GitOrigin-RevId: 64cc3fad53c8313ad2fb3f2ba2fd44f280e5babf
diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index e0a6d2f..aea8fda 100644
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -549,6 +549,7 @@
- Fix a crash in requires expression with templated base class member function. Fixes (#GH84020).
- Fix a crash caused by defined struct in a type alias template when the structure
has fields with dependent type. Fixes (#GH75221).
+- Fix the Itanium mangling of lambdas defined in a member of a local class (#GH88906)
Bug Fixes to AST Handling
^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/include/clang/Basic/LangOptions.h b/include/clang/Basic/LangOptions.h
index 24b109e..7556228 100644
--- a/include/clang/Basic/LangOptions.h
+++ b/include/clang/Basic/LangOptions.h
@@ -224,6 +224,11 @@
/// - the parameter list of a template template parameter
Ver17,
+ /// Attempt to be ABI-compatible with code generated by Clang 18.0.x.
+ /// This causes clang to revert some fixes to the mangling of lambdas
+ /// in the initializers of members of local classes.
+ Ver18,
+
/// Conform to the underlying platform's C and C++ ABIs as closely
/// as we can.
Latest
diff --git a/lib/AST/ItaniumMangle.cpp b/lib/AST/ItaniumMangle.cpp
index c3b98d2..106c69d 100644
--- a/lib/AST/ItaniumMangle.cpp
+++ b/lib/AST/ItaniumMangle.cpp
@@ -1062,26 +1062,23 @@
// ::= <local-name>
//
const DeclContext *DC = Context.getEffectiveDeclContext(ND);
+ bool IsLambda = isLambda(ND);
// If this is an extern variable declared locally, the relevant DeclContext
// is that of the containing namespace, or the translation unit.
// FIXME: This is a hack; extern variables declared locally should have
// a proper semantic declaration context!
- if (isLocalContainerContext(DC) && ND->hasLinkage() && !isLambda(ND))
+ if (isLocalContainerContext(DC) && ND->hasLinkage() && !IsLambda)
while (!DC->isNamespace() && !DC->isTranslationUnit())
DC = Context.getEffectiveParentContext(DC);
- else if (GetLocalClassDecl(ND)) {
+ else if (GetLocalClassDecl(ND) &&
+ (!IsLambda || isCompatibleWith(LangOptions::ClangABI::Ver18))) {
mangleLocalName(GD, AdditionalAbiTags);
return;
}
assert(!isa<LinkageSpecDecl>(DC) && "context cannot be LinkageSpecDecl");
- if (isLocalContainerContext(DC)) {
- mangleLocalName(GD, AdditionalAbiTags);
- return;
- }
-
// Closures can require a nested-name mangling even if they're semantically
// in the global namespace.
if (const NamedDecl *PrefixND = getClosurePrefix(ND)) {
@@ -1089,6 +1086,11 @@
return;
}
+ if (isLocalContainerContext(DC)) {
+ mangleLocalName(GD, AdditionalAbiTags);
+ return;
+ }
+
if (DC->isTranslationUnit() || isStdNamespace(DC)) {
// Check if we have a template.
const TemplateArgumentList *TemplateArgs = nullptr;
@@ -2201,8 +2203,6 @@
if (NoFunction && isLocalContainerContext(DC))
return;
- assert(!isLocalContainerContext(DC));
-
const NamedDecl *ND = cast<NamedDecl>(DC);
if (mangleSubstitution(ND))
return;
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 5531e93..8236051 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -3660,6 +3660,9 @@
case LangOptions::ClangABI::Ver17:
GenerateArg(Consumer, OPT_fclang_abi_compat_EQ, "17.0");
break;
+ case LangOptions::ClangABI::Ver18:
+ GenerateArg(Consumer, OPT_fclang_abi_compat_EQ, "18.0");
+ break;
case LangOptions::ClangABI::Latest:
break;
}
@@ -4167,6 +4170,8 @@
Opts.setClangABICompat(LangOptions::ClangABI::Ver15);
else if (Major <= 17)
Opts.setClangABICompat(LangOptions::ClangABI::Ver17);
+ else if (Major <= 18)
+ Opts.setClangABICompat(LangOptions::ClangABI::Ver18);
} else if (Ver != "latest") {
Diags.Report(diag::err_drv_invalid_value)
<< A->getAsString(Args) << A->getValue();
diff --git a/test/CodeGenCXX/mangle-lambdas-gh88906.cpp b/test/CodeGenCXX/mangle-lambdas-gh88906.cpp
new file mode 100644
index 0000000..e7592ce
--- /dev/null
+++ b/test/CodeGenCXX/mangle-lambdas-gh88906.cpp
@@ -0,0 +1,46 @@
+// RUN: %clang_cc1 -triple x86_64-linux-gnu %s -emit-llvm -mconstructor-aliases -o - | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fclang-abi-compat=18 %s -emit-llvm -mconstructor-aliases -o - | FileCheck --check-prefix=CLANG18 %s
+// RUN: %clang_cc1 -triple i386-pc-win32 %s -emit-llvm -mconstructor-aliases -o - | FileCheck --check-prefix=MSABI %s
+
+
+class func {
+public:
+ template <typename T>
+ func(T){};
+ template <typename T, typename U>
+ func(T, U){};
+};
+
+void GH88906(){
+ class Test{
+ public:
+ func a{[]{ }, []{ }};
+ func b{[]{ }};
+ func c{[]{ }};
+ } test;
+}
+
+// CHECK-LABEL: define internal void @_ZZ7GH88906vEN4TestC2Ev
+// CHECK: call void @_ZN4funcC2IN7GH889064Test1aMUlvE_ENS3_UlvE0_EEET_T0_
+// CHECK: call void @_ZN4funcC2IN7GH889064Test1bMUlvE_EEET_
+// CHECK: call void @_ZN4funcC2IN7GH889064Test1cMUlvE_EEET_
+
+// CHECK-LABEL: define internal void @_ZN4funcC2IN7GH889064Test1aMUlvE_ENS3_UlvE0_EEET_T0_
+// CHECK-LABEL: define internal void @_ZN4funcC2IN7GH889064Test1bMUlvE_EEET_
+// CHECK-LABEL: define internal void @_ZN4funcC2IN7GH889064Test1cMUlvE_EEET_
+
+// CLANG18-LABEL: define internal void @_ZZ7GH88906vEN4TestC2Ev
+// CLANG18: call void @_ZN4funcC2IZ7GH88906vEN4TestUlvE_EZ7GH88906vENS1_UlvE0_EEET_T0_
+// CLANG18: call void @_ZN4funcC2IZ7GH88906vEN4TestUlvE_EEET_
+// CLANG18: call void @_ZN4funcC2IZ7GH88906vEN4TestUlvE_EEET_
+
+
+
+// MSABI-LABEL: define internal x86_thiscallcc noundef ptr @"??0Test@?1??GH88906@@YAXXZ@QAE@XZ"
+// MSABI: call x86_thiscallcc noundef ptr @"??$?0V<lambda_1>@a@Test@?1??GH88906@@YAXXZ@V<lambda_2>@12?1??3@YAXXZ@@func@@QAE@V<lambda_1>@a@Test@?1??GH88906@@YAXXZ@V<lambda_2>@23?1??4@YAXXZ@@Z"
+// MSABI: call x86_thiscallcc noundef ptr @"??$?0V<lambda_1>@b@Test@?1??GH88906@@YAXXZ@@func@@QAE@V<lambda_1>@b@Test@?1??GH88906@@YAXXZ@@Z"
+// MSABI: call x86_thiscallcc noundef ptr @"??$?0V<lambda_1>@c@Test@?1??GH88906@@YAXXZ@@func@@QAE@V<lambda_1>@c@Test@?1??GH88906@@YAXXZ@@Z"
+
+// MSABI-LABEL: define internal x86_thiscallcc noundef ptr @"??$?0V<lambda_1>@a@Test@?1??GH88906@@YAXXZ@V<lambda_2>@12?1??3@YAXXZ@@func@@QAE@V<lambda_1>@a@Test@?1??GH88906@@YAXXZ@V<lambda_2>@23?1??4@YAXXZ@@Z"
+// MSABI-LABEL: define internal x86_thiscallcc noundef ptr @"??$?0V<lambda_1>@b@Test@?1??GH88906@@YAXXZ@@func@@QAE@V<lambda_1>@b@Test@?1??GH88906@@YAXXZ@@Z"
+// MSABI-LABEL: define internal x86_thiscallcc noundef ptr @"??$?0V<lambda_1>@c@Test@?1??GH88906@@YAXXZ@@func@@QAE@V<lambda_1>@c@Test@?1??GH88906@@YAXXZ@@Z"
