discriminant in velocity calculation error

Hi,
i got an error: discriminant -1.981264 < 0 in velocity calculation

i'm using LinuxCNC 2.8.0 pre1

Gcode in attachment (error is near line 24730)

thank you

I can duplicate this error. It seems sensitive to accel values

I pared it down to this snipit of gcode. It does violate acceleration constraints when it happens..

g21f1200
g0x0y0
g1X54.834 Y-52.151
X55.038 Y-59.286
G3 X58.636 Y-62.782 I3.598 J.103
X58.739 Y-62.781 I0. J3.599
X62.104 Y-60.15 I-.103 J3.598
G1 X62.158 Y-59.927 Z-3.31 F600.
X62.199 Y-59.701 Z-3.324
X62.376 Y-58.483 Z-3.403
X62.403 Y-58.242 Z-3.418
X62.413 Y-58.001 Z-3.433
X62.408 Y-57.759 Z-3.449
X62.386 Y-57.518 Z-3.464
X62.348 Y-57.279 Z-3.48
X62.294 Y-57.044 Z-3.495
G2 X62.121 Y-56.199 I7.25 J1.918
X62.069 Y-55.733 I7.423 J1.073
G1 X62.023 Y-55.583
m30

Accelleration needs to be set at 600mm/s^2 - my velocity was set to 211mm/s