[lldb] Ignore breakpoints by default in SBFrame::EvaluateExpression

[evgeny777]

Summary

This will help to correctly evaluate functions which throw language exceptions using lldb-mi

[evgeny777]

Greg, Enrico,

Can someone tell if it is possible to modify Python interface this way. Without this modification user breakpoints will be hit when someone evaluates expression and use Python interface. The lldb frontend ignores breakpoints, lldb-mi does not, becauses it uses SBFrame::EvaluateExpression in multimple places (for example in -data-evaluate-expression command). If it is not correct to apply this change in Python interface let me know - I'll implement a workaround in MI instead

[granata.enrico]

It looks like this code is default constructing a SBExpressionOptions(), which at the end of the day is a fancy wrapper for EvaluateExpressionOptions

This last object gets default constructed with

m_ignore_breakpoints (false),

I wonder whether that is a useful default value to begin with. My personal preference would be to change that default to be true and then everyone would by default get it "right" for what looks to me like the most common use case.

With that said, if there is a reason for that default to be what it is (and I don't know right now and am not in the office to ask), then your patch would seem reasonable to me as long as you make the same change in all overloads of EvaluateExpression() except the one that explicitly takes an SBExpressionOptions.

source/API/SBFrame.cpp

SBFrame::EvaluateExpression (const char *expr)
     StackFrame *frame = exe_ctx.GetFramePtr();
     Target *target = exe_ctx.GetTargetPtr();
     if (frame && target)
     {
         SBExpressionOptions options;
         lldb::DynamicValueType fetch_dynamic_value = frame->CalculateTarget()->GetPreferDynamicValue();
         options.SetFetchDynamicValue (fetch_dynamic_value);
         options.SetUnwindOnError (true);
+        options.SetIgnoreBreakpoints (true);
         if (target->GetLanguage() != eLanguageTypeUnknown)
             options.SetLanguage(target->GetLanguage());
         else
             options.SetLanguage(frame->GetLanguage());
         return EvaluateExpression (expr, options);
     }
     return result;
 }