the vsarduino file is to bump start the Visual Studio C++ intellisense for Arduino which does not know about the GCC compiler tool that will be used.

The compliation uses the real tool chain which is resonposible to setting many internal #defines.

It is possible to obtain an accurate list of defines for intellisense but that requires running a tool chain. exe in background which is quite slow. So we plan to save the info after each build and use that instead of forcing generic defines. That will bring othe issues because the Vc++ intellisense does not like GCC. Therefore we also need to switch to a new intellisense engine that MS are working on.

So for now there is not a perfect correlation between intellisense and real tool chains especially when working with non-arduino lower level syntax.

Thanks for your reply. You are right - Intellisense does not like GCC too much.
btw Intellisense does not like __GNUC__ etc. either, so I had to add them to vs-intellisense-fix.h
At least now nothing is complaining.

Tim@Visual Micro wrote on Sep 29^th, 2019 at 2:55pm:

I am using my own design board with an Atmega169PA and Optiboot bootloader.
I did not alter vsarduino.h but here is my vs-intellisense-fix.h

#if defined(_VMICRO_INTELLISENSE)
#define pgm_read_byte_near(address_short) uint8_t()
#define __GNUC__             5
#define __GNUC_MINOR__       4
#define __GNUC_PATCHLEVEL__  0
#endif 

This keeps Intellisense happy.

In my program I just use the predefined macros and they just work, eg.

ConsoleMsg(INFO,  PSTR("Compiled:   " __DATE__ " at " __TIME__ ", GCC v%d.%d.%d"), __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);
 

I also tried defining the following and it worked fine too;

#define GCC_VERSION ((__GNUC__*10000)+(__GNUC_MINOR__*100)+__GNUC_PATCHLEVEL__)) 

but as I wrote in the earlier post I could not find this definition anywhere in my GCC installation, so I had to define it myself. If it is not defined anywhere then it probably does not belong in vsarduino.h