Hello all,
See screenshot.
I have a project using a Teensy 3.x.
Anytime that I use the function abs (its actually a #define that is defined in wiring.h, one of the Teensyduino core files).
Visual studio flags it as an error. Hovering states "expected an expression".
The code compiles fine and everything works. It's annoying having errors and red blocks in the scrollbar at every place I've used "abs".
Does anyone know how to fix this?  Thanks.

The visual studio c++ intellisense does not understand some Gcc commands. Intellisense is handled by VS and build by Visual Micro which is why the build works.

It's possible to fool VS into being happy which I will do for abs for Teensy3 in the next release.

You can always report these things along with which hardware you are using because the way some of the methods are defined change per board/platform.

You can also provide the workaround yourself without affect your code.

http://www.visualmicro.com/page/Extending-Visual-Studio-Intellisense.aspx

Fixed in the next release due shortly.

An intellisense fix has been added for all functions found in the teensy3 wiring.h.

Intellisense will show the following but the compiler will use the real teensy code.

#define abs(x)
#define constrain(amt, low, high)
#define round(x)
#define radians(deg)
#define degrees(rad)
#define sq(x)