The best replacement for keil is sdcc.

The best alternatives to keil are rated as following:
★★★★★  sdcc
★★★★★  gcc
★★★★  iar
★★★★  coocox
★★★  mikroc
★★  crossworks
★★  codewarrior
★★  iar arm
★★  lpcxpresso
★★  ds-5
★  codesourcery

Your alternative for keil is not listed? Suggest!
Speaking about keil, one probably shouldn't forget about mbed.

Other search terms related to keil and their ratings are:
★★★★★ mbed
You have in mind a companion for keil and it is not yet here? Propose!



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keil
sdcc
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