https://github.com/Nerixyz created https://github.com/llvm/llvm-project/pull/175842
To look up an item in a `std::deque` we do https://github.com/llvm/llvm-project/blob/d69335bac9d218ed5dadeebed66b600347d5db8e/lldb/source/Plugins/Language/CPlusPlus/MsvcStlDeque.cpp#L71-L73 This will crash on if `m_block_size` or `m_map_size` is zero. We didn't check that these aren't zero. With this PR, we do. When running the MSVC STL smoke test, `m_map_size` was randomly zero (the test breaks before the variables are initialized) and the test failed, because LLDB crashed. >From 58ccd863bd2266d454c363f0f262213ecb1332ef Mon Sep 17 00:00:00 2001 From: Nerixyz <[email protected]> Date: Tue, 13 Jan 2026 21:52:03 +0100 Subject: [PATCH] [LLDB] Prevent division by zero in MSVC deque formatter --- lldb/source/Plugins/Language/CPlusPlus/MsvcStlDeque.cpp | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/lldb/source/Plugins/Language/CPlusPlus/MsvcStlDeque.cpp b/lldb/source/Plugins/Language/CPlusPlus/MsvcStlDeque.cpp index 7fd1e6691a4bd..de103e9e4a460 100644 --- a/lldb/source/Plugins/Language/CPlusPlus/MsvcStlDeque.cpp +++ b/lldb/source/Plugins/Language/CPlusPlus/MsvcStlDeque.cpp @@ -110,7 +110,7 @@ lldb_private::formatters::MsvcStlDequeSyntheticFrontEnd::Update() { if (!block_size_decl) return lldb::eRefetch; Scalar block_size = block_size_decl.GetConstantValue(); - if (!block_size.IsValid()) + if (!block_size.IsValid() || block_size <= 0) return lldb::eRefetch; ValueObjectSP offset_sp = storage_sp->GetChildMemberWithName("_Myoff"); @@ -126,7 +126,7 @@ lldb_private::formatters::MsvcStlDequeSyntheticFrontEnd::Update() { return lldb::eRefetch; uint64_t map_size = map_size_sp->GetValueAsUnsigned(0, &ok); - if (!ok) + if (!ok || map_size == 0) return lldb::eRefetch; uint64_t size = size_sp->GetValueAsUnsigned(0, &ok); _______________________________________________ lldb-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
