HTSOFT PICC18 vs uC MCC18

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Oznog

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I took a pretty large project which took 25k of a 32k PIC18F452 and modified it for compatability with MCC18, most of it was just a lot of #define replacements, reformatting the CONFIG bits, etc.

The ROM usage I had was considerably larger with MCC18. It took 30k, an additional 20%. I did a bit of monkeying, noticed that Integer Promotion was disabled by default. PICC18 doesn't have a way to disable it so the code might not be functionally equivalent where not explicitly cast. So I tried enabling Integer Promotion and the code became too large to compile with MCC18.

A lot of that code is constant font data and const screen page data which should not compile in a different size. Thus is seems the size of the executable code is more than 20% larger.

Has anyone else tried to compile for both? Is this typical? Or is there some way of compiling that would take less space?
 
Someone helped me out on Microchip's forum- the optimizations are on by default in the compiler, but the IDE interface default adds options to turn them off.

With all the optimizations enabled, it's now much better. The code is smaller than PICC18, but only slightly so, to the tune of around 2%.
 
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