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Why I cannot to choose some parts as breakpoint in the Keil? please consider to these pictures:



If you consider to some parts that I determined, you will know that I cannot to select those as a breakpoint. Why? some of them are function. that's odd to me.

Note that we can choose some parts that are determined with a gray square at the left but if you consider the parts that I determined don't have it.

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up vote 4 down vote accepted

That is because those lines were optimized out and not compiled into actual instructions. No machine instruction means nothing to break on. If you take a look into the disassembly window, you can see there is no assembly code associated with them.

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+1 and thanks to you and slap to my face! I don't know why I had not considered to this! – Roh Aug 25 '14 at 18:09
If you really want to break on those lines, or close to them you should add a __nop(); intrinsic, which generates a NOP instruction that you can set a breakpoint on. – Zuofu Aug 25 '14 at 18:13

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