I noticed a failure of [running LLDB test suites on Windows
AArch64](https://lab.llvm.org/buildbot/#/builders/219/builds/9849). The
failed test case is about
checking output of command `breakpoint list -v -L c++`, and an mismatch
on the demangled
name of a function occurred. The test case expects `ns::func(void)`, but
on Windows it is `int ns::func(void)`.
It results from the different mangling scheme used by MSVC, and the
comparison is as follows:
| Scheme | Mangled | Demangled (fully) | Note |
| --- | --- | --- | --- |
| MSVC | `?func@ns@@YAHXZ` | `int __cdecl ns::func(void)` |
[Godbolt](https://godbolt.org/z/5ns8c7xW3) (I have no available Windows
device) |
| Itanium | `_ZN2ns4funcEv` | `ns::func()` | |
According to the current use of MSVC demangling,
8f68022f8e/lldb/source/Core/Mangled.cpp (L128-L143)
the `__cdecl` specifier is not part of the name. However, the function's
parameter types should be present
as ` llvm::MSDF_NoVariableType` [does not affect a symbol for
functions](8f68022f8e/llvm/lib/Demangle/MicrosoftDemangleNodes.cpp (L417-L453)).
Therefore, it is inappropriate to assume the demangled name are the same
on all platforms. Instead of tweaking the
existing code of demangling to get the same (demangled) name, I think it
is more reasonable to modify the test case.