Enable lldb to step-in into message forwarding machinery

Originator:pohilets
Number:rdar://27883849 Date Originated:17-Aug-2016 11:56 AM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 7.3.1 (7D1014)
Classification:Feature (New) Reproducible:Always
 
Summary:
Debugging code that uses message forwarding is very inconvenient - currently it requires either going through lots of assembly code or manually inspecting sender and putting breakpoints into appropriate places.

Steps to Reproduce:
A.
1. When debugging in the Xcode, get to the line where method implemented through message forwarding is called.
2. Step-in

B.
1. When debugging in the Xcode, get to the line where -[NSInvocation invoke] is called
2. Step-in

Expected Results:
A.
Debugger should stop in one of the -forwardingTargetForSelector:, -methodSignatureForSelector:, methodSignatureForSelector:

B. Debugger should stop in the method being called by NSInvocation

Actual Results:
Debugger steps over

Comments


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