how is the performance between KDS newlib/newlib-nano and Codewarrior ewl library ? code size and speed.
this is a very general question, and there is no clear answer to your question. Code and data size are heavily influenced how you write your code, and especially how you use the library (e.g. printf() or other calls). I think you will need to test it with your real application. Porting a CodeWarrior project to KDS is not that hard, so to get accurate data, I recommend that you make that effort.
The differences are not only because of the libraries, as well because of the compilers used.
Have a read what is discussed in this thread: https://community.freescale.com/thread/323332
Additionally here: Comparing CodeWarrior with Kinetis Design Studio
I hope this helps,
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