https://github.com/alejandro-alvarez-sonarsource created
https://github.com/llvm/llvm-project/pull/121550
An instantiated templated function definition may not have a body due to
parsing errors inside the templated function. When serializing, an assert is
triggered inside `ASTRecordWriter::AddFunctionDefinition`.
The instantiation may happen on an intermediate module.
The test case was reduced from `mp-units`.
From fe4adf2f95aeb72436eead3567767c8c539811c3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alejandro=20=C3=81lvarez=20Ayll=C3=B3n?=
<alejandro.alva...@sonarsource.com>
Date: Fri, 3 Jan 2025 08:58:23 +0100
Subject: [PATCH] [clang] Do not serialize function definitions without a body
An instantiated templated function definition may not have a body due
to parsing errors inside the templated function. When serializing, an
assert is tripped inside `ASTRecordWriter::AddFunctionDefinition` when
building with assertions enabled.
The instantiation may happen on an intermediate module.
The test case was reduced from `mp-units`.
---
clang/lib/Serialization/ASTWriter.cpp | 6 ++-
clang/test/Modules/missing-body-in-import.cpp | 42 +++++++++++++++++++
2 files changed, 46 insertions(+), 2 deletions(-)
create mode 100644 clang/test/Modules/missing-body-in-import.cpp
diff --git a/clang/lib/Serialization/ASTWriter.cpp
b/clang/lib/Serialization/ASTWriter.cpp
index 4a6027943072c0..36b9e3e2ba1720 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -6227,8 +6227,10 @@ void ASTWriter::WriteDeclUpdatesBlocks(ASTContext
&Context,
// Add a trailing update record, if any. These must go last because we
// lazily load their attached statement.
if (!GeneratingReducedBMI || !CanElideDeclDef(D)) {
- if (HasUpdatedBody) {
- const auto *Def = cast<FunctionDecl>(D);
+ assert(!(HasUpdatedBody && HasAddedVarDefinition) &&
+ "Declaration can not be both a FunctionDecl and a VarDecl");
+ if (const auto *Def = dyn_cast<FunctionDecl>(D);
+ HasUpdatedBody && Def->doesThisDeclarationHaveABody()) {
Record.push_back(UPD_CXX_ADDED_FUNCTION_DEFINITION);
Record.push_back(Def->isInlined());
Record.AddSourceLocation(Def->getInnerLocStart());
diff --git a/clang/test/Modules/missing-body-in-import.cpp
b/clang/test/Modules/missing-body-in-import.cpp
new file mode 100644
index 00000000000000..b52ebba15087a3
--- /dev/null
+++ b/clang/test/Modules/missing-body-in-import.cpp
@@ -0,0 +1,42 @@
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: cd %t
+
+// RUN: %clang_cc1 -std=c++23 mod1.cppm -emit-module-interface -o mod1.pcm
-fallow-pcm-with-compiler-errors -verify
+// RUN: %clang_cc1 -std=c++23 mod2.cppm -emit-module-interface -o mod2.pcm
-fmodule-file=mod1=mod1.pcm -verify -fallow-pcm-with-compiler-errors
+// RUN: %clang_cc1 -std=c++23 mod3.cppm -emit-module-interface -o mod3.pcm
-fmodule-file=mod1=mod1.pcm -fmodule-file=mod2=mod2.pcm -verify
-fallow-pcm-with-compiler-errors
+// RUN: %clang_cc1 -std=c++23 main.cpp -fmodule-file=mod1=mod1.pcm
-fmodule-file=mod2=mod2.pcm -fmodule-file=mod3=mod3.pcm -verify
-fallow-pcm-with-compiler-errors -ast-dump-all
+
+//--- mod1.cppm
+export module mod1;
+
+export template <unsigned N, unsigned M>
+class A {
+public:
+ constexpr A(const char[], const char[]) {
+ auto x = BrokenExpr; // expected-error {{use of undeclared identifier
'BrokenExpr'}}
+ }
+};
+
+export template<A<1,1> NTTP>
+struct B {};
+
+template < unsigned N, unsigned M >
+A(const char (&)[N], const char (&)[M]) -> A< 1, 1 >;
+
+//--- mod2.cppm
+export module mod2;
+import mod1;
+
+struct C: B <A{"a", "b"}> { // expected-error {{non-type template argument is
not a constant expression}}
+ constexpr C(int a) { }
+};
+
+//--- mod3.cppm
+// expected-no-diagnostics
+export module mod3;
+export import mod2;
+
+//--- main.cpp
+// expected-no-diagnostics
+import mod3; // no crash
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
