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'm using lldb to debug objc based service. several breakpoints (which is set have been placed in the code, and I see that one of them is reached unexpectedly according to the stack trace.

The method encapsulating this breakpoint shouldn't have called but I still see it in stack trace (file1.mm:97) although it seems like the code isn't being execute there.

I suspect that objc internal method _Block_byref_object_copy is responsible for copying the block of code which involves both caller and callee methods (MyClass from the upper frame in the stack and the method in file1.mm:97).

While copying the debugger probably thinks that it reach this line for execution and stop there, where in fact it's only for copying the code block which involves those 2 methods.

Perhaps anybody can support this claim or provide additional explanation of why am I getting this breakpoint where it shouldn't occur ?

  * frame #0: 0x0000000107e03ce0 MyLib`::__Block_byref_object_copy_((null)=0x00007fda19a86b30, (null)=0x00007ffeea7f3bd0) at file1.mm:97:27
    frame #1: 0x00007fff7de6bb78 libsystem_blocks.dylib`_Block_object_assign + 325
    frame #2: 0x0000000107dd960a MyLib`::__copy_helper_block_ea8_32r((null)=0x00007fda19a86540, (null)=0x00007ffeea7f3ba8) at file2.mm:47:55
    frame #3: 0x00007fff7de6b9f3 libsystem_blocks.dylib`_Block_copy + 104
    frame #4: 0x00007fff7c64e1e8 libobjc.A.dylib`objc_setProperty_atomic_copy + 53
    frame #5: 0x00007fff5411d16b Foundation`-[NSXPCConnection _sendInvocation:orArguments:count:methodSignature:selector:withProxy:] + 1885
    frame #6: 0x00007fff54168508 Foundation`-[NSXPCConnection _sendSelector:withProxy:arg1:arg2:] + 125
    frame #7: 0x00007fff54168485 Foundation`_NSXPCDistantObjectSimpleMessageSend2 + 46
    frame #8: 0x0000000107e0520e MyLib`::-[MyClass func:withVar0:Var1:Var2:withError:](self=0x00007fda17c2cb50, _cmd="funcWithVar0:Var1:Var2:Var3:withError:", var0="aaa", var1=0x0000000000000000, var2="bbb", var3=0x00007fda17d41dd0, err=0x00007ffeea7f4258) at MyClass.mm:196:5

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