https://github.com/AZero13 created https://github.com/llvm/llvm-project/pull/221603
The fake-use coroutine check in EmitParmDecl calls FnDecl->getBody()->getStmtClass() without guarding against a null getBody(). This crashes when processing implicit parameters (e.g. should_call_delete) of MSVC deleting destructors whose base destructor is only declared, not defined. >From 9cb39933030d5081fde92c2c1dfe0621e4615a9e Mon Sep 17 00:00:00 2001 From: AZero13 <[email protected]> Date: Wed, 26 Aug 2026 14:24:55 -0400 Subject: [PATCH] [Clang][CodeGen] Fix crash in EmitParmDecl for bodyless destructors with -fextend-variable-liveness (#218830) The fake-use coroutine check in EmitParmDecl calls FnDecl->getBody()->getStmtClass() without guarding against a null getBody(). This crashes when processing implicit parameters (e.g. should_call_delete) of MSVC deleting destructors whose base destructor is only declared, not defined. --- clang/docs/ReleaseNotes.md | 1 + clang/lib/CodeGen/CGDecl.cpp | 2 +- clang/test/CodeGen/fake-use-msvc-dtor.cpp | 17 +++++++++++++++++ 3 files changed, 19 insertions(+), 1 deletion(-) create mode 100644 clang/test/CodeGen/fake-use-msvc-dtor.cpp diff --git a/clang/docs/ReleaseNotes.md b/clang/docs/ReleaseNotes.md index 6928e8ab4bffb..d3039f0091e91 100644 --- a/clang/docs/ReleaseNotes.md +++ b/clang/docs/ReleaseNotes.md @@ -998,6 +998,7 @@ latest release, please see the [Clang Web Site](https://clang.llvm.org) or the - Fixed a crash when passing one sized implicitly casted vector to a `abs` function. (#GH204777) - Fixed a crash when diagnosing an invalid out-of-line definition of a member class template. (#GH201490) - Fixed a crash in the parser when a missing semicolon after a tag definition is followed by a template-id not preceded by `::`. (#GH207992) +- Fixed a crash when generating fake uses for parameters of bodyless destructors with `-fextend-variable-liveness`. ### OpenACC Specific Changes diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp index 29bc47130c4cd..e84e05e8ee0fd 100644 --- a/clang/lib/CodeGen/CGDecl.cpp +++ b/clang/lib/CodeGen/CGDecl.cpp @@ -2856,7 +2856,7 @@ void CodeGenFunction::EmitParmDecl(const VarDecl &D, ParamValue Arg, &D == CXXABIThisDecl)) { // We don't emit fake uses for coroutine parameters, other than `this`. if (auto *FnDecl = dyn_cast_or_null<FunctionDecl>(CurCodeDecl); - &D == CXXABIThisDecl || !FnDecl || + &D == CXXABIThisDecl || !FnDecl || !FnDecl->getBody() || FnDecl->getBody()->getStmtClass() != Stmt::CoroutineBodyStmtClass) { if (shouldExtendLifetime(getContext(), CurCodeDecl, D, CXXABIThisDecl)) EHStack.pushCleanup<FakeUse>(NormalFakeUse, DeclPtr); diff --git a/clang/test/CodeGen/fake-use-msvc-dtor.cpp b/clang/test/CodeGen/fake-use-msvc-dtor.cpp new file mode 100644 index 0000000000000..3988b4b2242ec --- /dev/null +++ b/clang/test/CodeGen/fake-use-msvc-dtor.cpp @@ -0,0 +1,17 @@ +// RUN: %clang_cc1 %s -triple x86_64-pc-windows-msvc -emit-llvm -fextend-variable-liveness=all -O1 -mconstructor-aliases -o /dev/null +// Verify that we do not crash when generating fake uses for parameters +// of destructor declarations that have no body (the should_call_delete +// implicit parameter in MSVC deleting destructors). + +struct A { + virtual ~A(void); +}; +struct B { + virtual ~B(void); +}; + +struct C : A, B {}; + +void foo() { + C c; +} _______________________________________________ llvm-branch-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
