How to Turn Off All Optimizations/Eliminate SP debug info incorrect warning/etc

[YeOldeBDM]

Hi. I am using CodeWarrior 3.1 for HCS12.

I am having some problems with promotions to longs, the way certain #define's are taken when their size is not specified, etc mysterious results when an unsigned char member of a structure is a multiplicand versus a standalone unsigned char, understanding what is implementation dependent and what is not, AND ALL THAT GOOD STUFF.

I am experimenting with various snippets of code, and all too often the optimizations are obfuscating what is observed in the debugger.

Is there a way to setup a project so that all optimization is turned off (just for that project) ?

If there is no way to localize the compiler settings to that one project, can someone explain to me how to turn off all the optimizations anyway?

Thanks

[CrasyCat · Accepted solution]

Hello

The symptoms you are describing are not directly related to optimization but rather to ANSI C standard definition.

You say "promotions to longs, the way certain #defines are taken when their size is not specified".

Please remember that ANSI C standard defines that integral promotion rule apply for arithmetic operation which do not involve a long operand.

That means if you have an assignment as follows:

  myLong = myInt1*myInt2;

the expression myInt1*myInt2 will be evaluated on 16-bit and then signed extended to 32-bits.

To make sure the expression is evaluated on 32-bits, you have to cast one of the operands as a long.

This is done as follows:

  myLong = (long)myInt1*myInt2;

for operand defined as macro (in a define), just add the suffix L to the constant to make sure it is interpreted as  a long.

For example

#define myInt1     10L

If you really want to disable optimization proceed as follows:

   - Open the project in the IDE

   - Open the Target Settings dialog (Press ALT + F7)

   - Switch to "Compiler for HC12" panel

   - Click on the "Options" button

   - THere are a lot of optimization you can disable there. This will be taken only for the current project.

However note that some optimization cannot be disable at al.

I hope this helps.

CrasyCat