fix-149477-- Emit correct closure members for lambdas in CreateLimitedType

[ayushpareek2003]

Fix an issue where local lambdas caused a crash when importing the std module in LLDB due to missing capture fields in debug info.
Now closures always emit all fields for lambdas by skipping the isImplicit check.
This unblocks libc++ from using local lambdas freely

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[llvmbot]

@llvm/pr-subscribers-clang

Author: Ayush Pareek (ayushpareek2003)

Changes

Fix an issue where local lambdas caused a crash when importing the std module in LLDB due to missing capture fields in debug info.
Now closures always emit all fields for lambdas by skipping the isImplicit check.
This unblocks libc++ from using local lambdas freely

---

Full diff: https://github.com/llvm/llvm-project/pull/149674.diff

1 Files Affected:

• (modified) clang/lib/CodeGen/CGDebugInfo.cpp (+26)

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index e24c68ed02865..a8f9e3e028e9f 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -4187,6 +4187,32 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
   RegionMap[Ty->getDecl()].reset(RealDecl);
   TypeCache[QualType(Ty, 0).getAsOpaquePtr()].reset(RealDecl);
 
+  if (const auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
+    SmallVector<llvm::Metadata *, 16> EltTys;
+    const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(CXXRD);
+
+    for (const FieldDecl *Field : CXXRD->fields()) {
+      if (!CXXRD->isLambda() && Field->isImplicit())
+        continue;
+
+      llvm::DIType *FieldType = getOrCreateType(Field->getType(), DefUnit);
+      unsigned FieldLine = getLineNumber(Field->getLocation());
+      uint64_t FieldOffset = Layout.getFieldOffset(Field->getFieldIndex());
+      llvm::DIFile *FieldFile = DefUnit;
+
+      llvm::DIDerivedType *Elem = DBuilder.createMemberType(
+          RealDecl, Field->getName(), FieldFile, FieldLine,
+          CGM.getContext().getTypeSize(Field->getType()),
+          getTypeAlignIfRequired(Field->getType(), CGM.getContext()),
+          FieldOffset,
+          getAccessFlag(Field->getAccess()), FieldType);
+
+      EltTys.push_back(Elem);
+    }
+    // Attach the fields.
+    DBuilder.replaceArrays(RealDecl, DBuilder.getOrCreateArray(EltTys));
+  }
+
   if (const auto *TSpecial = dyn_cast<ClassTemplateSpecializationDecl>(RD))
     DBuilder.replaceArrays(RealDecl, llvm::DINodeArray(),
                            CollectCXXTemplateParams(TSpecial, DefUnit));

[llvmbot]

@llvm/pr-subscribers-debuginfo

Author: Ayush Pareek (ayushpareek2003)

Changes

Fix an issue where local lambdas caused a crash when importing the std module in LLDB due to missing capture fields in debug info.
Now closures always emit all fields for lambdas by skipping the isImplicit check.
This unblocks libc++ from using local lambdas freely

---

Full diff: https://github.com/llvm/llvm-project/pull/149674.diff

1 Files Affected:

• (modified) clang/lib/CodeGen/CGDebugInfo.cpp (+26)

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index e24c68ed02865..a8f9e3e028e9f 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -4187,6 +4187,32 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
   RegionMap[Ty->getDecl()].reset(RealDecl);
   TypeCache[QualType(Ty, 0).getAsOpaquePtr()].reset(RealDecl);
 
+  if (const auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
+    SmallVector<llvm::Metadata *, 16> EltTys;
+    const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(CXXRD);
+
+    for (const FieldDecl *Field : CXXRD->fields()) {
+      if (!CXXRD->isLambda() && Field->isImplicit())
+        continue;
+
+      llvm::DIType *FieldType = getOrCreateType(Field->getType(), DefUnit);
+      unsigned FieldLine = getLineNumber(Field->getLocation());
+      uint64_t FieldOffset = Layout.getFieldOffset(Field->getFieldIndex());
+      llvm::DIFile *FieldFile = DefUnit;
+
+      llvm::DIDerivedType *Elem = DBuilder.createMemberType(
+          RealDecl, Field->getName(), FieldFile, FieldLine,
+          CGM.getContext().getTypeSize(Field->getType()),
+          getTypeAlignIfRequired(Field->getType(), CGM.getContext()),
+          FieldOffset,
+          getAccessFlag(Field->getAccess()), FieldType);
+
+      EltTys.push_back(Elem);
+    }
+    // Attach the fields.
+    DBuilder.replaceArrays(RealDecl, DBuilder.getOrCreateArray(EltTys));
+  }
+
   if (const auto *TSpecial = dyn_cast<ClassTemplateSpecializationDecl>(RD))
     DBuilder.replaceArrays(RealDecl, llvm::DINodeArray(),
                            CollectCXXTemplateParams(TSpecial, DefUnit));

[llvmbot]

@llvm/pr-subscribers-clang-codegen

Author: Ayush Pareek (ayushpareek2003)

Changes

Fix an issue where local lambdas caused a crash when importing the std module in LLDB due to missing capture fields in debug info.
Now closures always emit all fields for lambdas by skipping the isImplicit check.
This unblocks libc++ from using local lambdas freely

---

Full diff: https://github.com/llvm/llvm-project/pull/149674.diff

1 Files Affected:

• (modified) clang/lib/CodeGen/CGDebugInfo.cpp (+26)

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index e24c68ed02865..a8f9e3e028e9f 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -4187,6 +4187,32 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
   RegionMap[Ty->getDecl()].reset(RealDecl);
   TypeCache[QualType(Ty, 0).getAsOpaquePtr()].reset(RealDecl);
 
+  if (const auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
+    SmallVector<llvm::Metadata *, 16> EltTys;
+    const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(CXXRD);
+
+    for (const FieldDecl *Field : CXXRD->fields()) {
+      if (!CXXRD->isLambda() && Field->isImplicit())
+        continue;
+
+      llvm::DIType *FieldType = getOrCreateType(Field->getType(), DefUnit);
+      unsigned FieldLine = getLineNumber(Field->getLocation());
+      uint64_t FieldOffset = Layout.getFieldOffset(Field->getFieldIndex());
+      llvm::DIFile *FieldFile = DefUnit;
+
+      llvm::DIDerivedType *Elem = DBuilder.createMemberType(
+          RealDecl, Field->getName(), FieldFile, FieldLine,
+          CGM.getContext().getTypeSize(Field->getType()),
+          getTypeAlignIfRequired(Field->getType(), CGM.getContext()),
+          FieldOffset,
+          getAccessFlag(Field->getAccess()), FieldType);
+
+      EltTys.push_back(Elem);
+    }
+    // Attach the fields.
+    DBuilder.replaceArrays(RealDecl, DBuilder.getOrCreateArray(EltTys));
+  }
+
   if (const auto *TSpecial = dyn_cast<ClassTemplateSpecializationDecl>(RD))
     DBuilder.replaceArrays(RealDecl, llvm::DINodeArray(),
                            CollectCXXTemplateParams(TSpecial, DefUnit));