[lldb] Ignore linkage diagnostic for LLDBSwigPythonBreakpointCallbackFunction (NFC)

[kastiglione]

Summary

Ignore -Wreturn-type-c-linkage diagnostics for LLDBSwigPythonBreakpointCallbackFunction.

The function is defined in python-wrapper.swig which uses extern "C" { ... } blocks.
The declaration of this function in ScriptInterpreterPython.cpp already uses these
same pragmas to silence the warning there.

This prevents -Werror builds from failing.

lldb/bindings/python/python-wrapper.swig

 // foo.bar.baz.Foobar to an actual Python object
 // if pmodule is NULL, the __main__ module will be used
 // as the starting point for the search
 
 
 // This function is called by lldb_private::ScriptInterpreterPython::BreakpointCallbackFunction(...)
 // and is used when a script command is attached to a breakpoint for execution.
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wreturn-type-c-linkage"
+
+// Disable warning C4190: 'LLDBSwigPythonBreakpointCallbackFunction' has
+// C-linkage specified, but returns UDT 'llvm::Expected<bool>' which is
+// incompatible with C
+#if _MSC_VER
+#pragma warning (push)
+#pragma warning (disable : 4190)
+#endif
+
 SWIGEXPORT llvm::Expected<bool>
 LLDBSwigPythonBreakpointCallbackFunction
 (
     const char *python_function_name,
     const char *session_dictionary_name,
     const lldb::StackFrameSP& frame_sp,
     const lldb::BreakpointLocationSP& bp_loc_sp,
     lldb_private::StructuredDataImpl *args_impl
)
 
     if (!result)
         return result.takeError();
 
     // Only False counts as false!
     return result.get().get() != Py_False;
 }
 
+#if _MSC_VER
+#pragma warning (pop)
+#endif
+
+#pragma clang diagnostic pop
+
 // This function is called by lldb_private::ScriptInterpreterPython::WatchpointCallbackFunction(...)
 // and is used when a script command is attached to a watchpoint for execution.
 
 SWIGEXPORT bool
 LLDBSwigPythonWatchpointCallbackFunction
 (
     const char *python_function_name,
     const char *session_dictionary_name,