If a server does not support allocating memory in an inferior process or
when debugging a core file, evaluating an expression in the context of a
value object results in an error:
```
error: <lldb wrapper prefix>:43:1: use of undeclared identifier '$__lldb_class'
43 | $__lldb_class::$__lldb_expr(void *$__lldb_arg)
| ^
```
Such expressions require a live address to be stored in the value
object. However, `EntityResultVariable::Dematerialize()` only sets
`ret->m_live_sp` if JIT is available, even if the address points to the
process memory and no custom allocations were made. Similarly,
`EntityPersistentVariable::Dematerialize()` tries to deallocate memory
based on the same check, resulting in an error if the memory was not
previously allocated in `EntityPersistentVariable::Materialize()`.
As an unintended bonus, the patch also fixes a FIXME case in
`TestCxxChar8_t.py`.
This will make changes in #145599 a bit nicer.
The problem was in calling GetLoadAddress on a value in the error state, where `ValueObject::GetLoadAddress` could end up accessing the uninitialized "address type" by-ref return value from `GetAddressOf`. This probably happened because each function expected the other to initialize it. We can guarantee initialization by turning this into a proper return value. I've added a test, but it only (reliably) crashes if lldb is built with ubsan.
This patch pushes the error handling boundary for the GetBitSize() methods from Runtime into the Type and CompilerType APIs. This makes it easier to diagnose problems thanks to more meaningful error messages being available. GetBitSize() is often the first thing LLDB asks about a type, so this method is particularly important for a better user experience. rdar://145667239
Co-authored-by: Jonas Devlieghere <jonas@devlieghere.com>
ValueObject is part of lldbCore for historical reasons, but conceptually
it deserves to be its own library. This does introduce a (link-time) circular
dependency between lldbCore and lldbValueObject, which is unfortunate
but probably unavoidable because so many things in LLDB rely on
ValueObject. We already have cycles and these libraries are never built
as dylibs so while this doesn't improve the situation, it also doesn't
make things worse.
The header includes were updated with the following command:
```
find . -type f -exec sed -i.bak "s%include \"lldb/Core/ValueObject%include \"lldb/ValueObject/ValueObject%" '{}' \;
```
This patch removes all of the Set.* methods from Status. This cleanup is part of a series of patches that make it harder use the anti-pattern of keeping a long-lives Status object around and updating it while dropping any errors it contains on the floor. This patch is largely NFC, the more interesting next steps this enables is to: 1. remove Status.Clear() 2. assert that Status::operator=() never overwrites an error 3. remove Status::operator=() Note that step (2) will bring 90% of the benefits for users, and step (3) will dramatically clean up the error handling code in various places. In the end my goal is to convert all APIs that are of the form ` ResultTy DoFoo(Status& error) ` to ` llvm::Expected<ResultTy> DoFoo() ` How to read this patch? The interesting changes are in Status.h and Status.cpp, all other changes are mostly ` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git grep -l SetErrorString lldb/source) ` plus the occasional manual cleanup.
I ran into issues with linking downstream language plugin to liblldb in debug builds, hitting link time errors of form: ``` undefined reference to `vtable for lldb_private::<Insert LLDB class here>' ``` Anchoring the vtable to the .cpp files resolved those issues. Differential Revision: https://reviews.llvm.org/D147252
This patch replaces (llvm::|)Optional< with std::optional<. I'll post a separate patch to clean up the "using" declarations, #include "llvm/ADT/Optional.h", etc. This is part of an effort to migrate from llvm::Optional to std::optional: https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716