What do the __CC_ARM, __ICCARM__, __GNUC__ and __TASKING__ macros mean?

Question

I am working on STM32l151rct6a by stm, I have stumbled upon these MACRO definitions

__CC_ARM, __ICCARM__, __GNUC__, __TASKING__

Does anyone kno

Answer 1

These are different compilers for ARM processors, probably these macros are used to hide compiler-dependent stuff in code that's compilable by several compilers.

• ICCARM --> IAR (there will also be a macro __IAR_SYSTEMS_ICC__ that is set to the compiler platform version
• __IMAGECRAFT__ --> Imagecraft C (also see Clifford's comments below - there's also a macro __ICC_VERSION__, see the pdf documentation)
• TASKING --> Tasking
• __CC_ARM --> ARM's (RealView) compiler
• __GNUC__ --> gcc

Answer 2

These are compiler specific MACROS and defined in compiler code.For example __ICC is for IAR and __GNU is for GNU compilers.There are some code given in BSP part for STM platform which have dependency on compilers.

Answer 3

They are macros for identifying the compiler being used to build the code.

A list of such macros, and others for identifying architecture and OS etc. can be found at http://sourceforge.net/p/predef/wiki/Home/. It does not however comprehensively cover many compilers from smaller embedded systems vendors (Tasking and Imagecraft for example).