Some later toolchains see a "const" data type as something different, even though it is not. Many older Arduino projects fail to compile because of the "const" issue. Visual Studio doesn't see a difference because the data type is the same. Both are far pointers to a float.

Visual Studio cannot know some finer detail such as that is built into the actual tool chain .exe and is not defined in external sources. For this reason  Visual Studio can only give 99% accuracy with intellisense. The alternative would be to run the actual tool chain in background while you are coding, that is a huge overhead especially for slower toolchains.

Visual Studio maintains a database for fast intellisense lookups, therefore we have to forgive it some inaccurancy. 

As you have noted, you can rely on the Visual Micro build process to give accurate results because it uses the toolchain directly without involvement from Visual Studio. 

There are other differences you will find between a real build and intellisense. That is because Visual Studio does not understand some of the underlying Gcc code that some toolchains use.

We can improve some areas of intellisense but some areas are beyond what can be achieved. We will look into this but it might be one of those ones we cannot cater for.

Hallo Simon

Current vMicro version causes errors in Teensy 4.1's RAM management. Patches with band-limited PWM waveforms can no longer be loaded. system hangs. 

It is probably due to my large program code. The display of free ITCM RAM1 (fast code) in Teensy 4.1 is same with old and new vMicro version. In the old version of vMicro, the code for calculating bandlimited waveforms is faster and doesn't crash. In the new version the code is very slow and the band limited waveforms cannot be calculated fast enough.