I can use the debugger without issue but when I use the attachinterrupt() function, I get the following:

Error linking for board ATmega2560 (Mega 2560) (Arduino Mega)                                                                       (mega_atmega2560)
WInterrupts.c.o (symbol from plugin)*: In function attachInterrupt
(.text+0x0)*: multiple definition of __vector_1
avr8-stub.c.o (symbol from plugin)*: (.text+0x0): first defined here
 
collect2.exe*: error: ld returned 1 exit status

If I try changing interrupts in the avr8-stub.h file, the vector number keeps changing but still does not compile.

Is this a limitation ?

I've attached multiple build files, with and without the attachinterrupt() files being referenced in the project. In addition, I'm including both the .h and .cpp files.

The main.ino file is not even calling the functions, just having them referenced causes this error. Note: The files work perfectly using the standard Serial Debugger.

The 2 functions to look at are: 
boolean FreqMeas_init(u8 pin, pin_change_dir dir, boolean use_average = true)
The above attaches the pin and call function.

static void transistions(void)
This is the attached interrupt function

Note: due to multiple files, I rolled them into a .zip

Hope this helps...
Thanks

See previous message, I use it and it works perfectly. A few of the things I miss:
- single stepping, step into..etc
- on the fly adding break points

I'm just glad you developed this full featured tool. The above items are missed but a small price to pay. My inquiry was just to check if I was missing something.

Thanks