[clang] Propagate definition data to all redecls

[hahnjo]

Fix the propagation added in commit 0d490ae to include all redecls, not only previous ones. This fixes another instance of the assertion "Cannot get layout of forward declarations" in getASTRecordLayout().

Kudos to Alexander Kornienko for providing an initial version of the reproducer that I further simplified.

Fixes #170084

[llvmbot]

@llvm/pr-subscribers-clang

@llvm/pr-subscribers-clang-modules

Author: Jonas Hahnfeld (hahnjo)

Changes

Fix the propagation added in commit 0d490ae to include all redecls, not only previous ones. This fixes another instance of the assertion "Cannot get layout of forward declarations" in getASTRecordLayout().

Kudos to Alexander Kornienko for providing an initial version of the reproducer that I further simplified.

Fixes #170084

---

Full diff: https://github.com/llvm/llvm-project/pull/170090.diff

2 Files Affected:

• (modified) clang/lib/Serialization/ASTReaderDecl.cpp (+2-2)
• (added) clang/test/Modules/GH170084.cpp (+75)

diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp index 5456e73956659..882d54f31280a 100644 --- a/clang/lib/Serialization/ASTReaderDecl.cpp +++ b/clang/lib/Serialization/ASTReaderDecl.cpp @@ -2107,8 +2107,8 @@ void ASTDeclMerger::MergeDefinitionData( auto *Def = DD.Definition; DD = std::move(MergeDD); DD.Definition = Def; - while ((Def = Def->getPreviousDecl())) - cast<CXXRecordDecl>(Def)->DefinitionData = &DD; + for (auto *D : Def->redecls()) + cast<CXXRecordDecl>(D)->DefinitionData = &DD; return; } diff --git a/clang/test/Modules/GH170084.cpp b/clang/test/Modules/GH170084.cpp new file mode 100644 index 0000000000000..950499467a6bb --- /dev/null +++ b/clang/test/Modules/GH170084.cpp @@ -0,0 +1,75 @@ +// RUN: rm -rf %t +// RUN: mkdir -p %t +// RUN: split-file %s %t +// RUN: cd %t + +// RUN: %clang_cc1 -fmodule-name=stl -fno-cxx-modules -emit-module -fmodules -xc++ stl.cppmap -o stl.pcm +// RUN: %clang_cc1 -fmodule-name=d -fno-cxx-modules -emit-module -fmodules -fmodule-file=stl.pcm -xc++ d.cppmap -o d.pcm +// RUN: %clang_cc1 -fmodule-name=b -fno-cxx-modules -emit-module -fmodules -fmodule-file=stl.pcm -xc++ b.cppmap -o b.pcm +// RUN: %clang_cc1 -fmodule-name=a -fno-cxx-modules -emit-module -fmodules -fmodule-file=stl.pcm -fmodule-file=d.pcm -fmodule-file=b.pcm -xc++ a.cppmap -o a.pcm +// RUN: %clang_cc1 -fno-cxx-modules -fmodules -fmodule-file=a.pcm -emit-llvm -o /dev/null main.cpp + +//--- a.cppmap +module "a" { +header "a.h" +} + +//--- a.h +#include "b.h" +namespace { +void a(absl::set<char> c) { + absl::set<int> b; + c.end(); + c.contains(); +} +} // namespace + +//--- b.cppmap +module "b" { +header "b.h" +} + +//--- b.h +#include "c.h" +void b() { absl::set<char> x; } + +//--- c.h +#include "stl.h" +namespace absl { +template <typename> +class set { + public: + struct iterator { + void u() const; + }; + iterator end() const { return {}; } + void contains() const { end().u(); } + pair<iterator> e(); +}; +} // namespace absl + +//--- d.cppmap +module "d" { +header "d.h" +} + +//--- d.h +#include "c.h" +void d() { absl::set<char> x; } + +//--- stl.cppmap +module "stl" { +header "stl.h" +} + +//--- stl.h +#ifndef _STL_H_ +#define _STL_H_ +template <class> +struct pair; +#endif + +//--- main.cpp +// expected-no-diagnostics +#include "c.h" +void f(absl::set<char> o) { o.contains(); } 

[vgvassilev]

LGTM!