Strange subroutine error

[code]o<drill1> sub

(info: Drilling bottom edge with horizontal spindle)

#<X_Coord> = #1 (X Coordinate)
#<Y_Coord> = #2 (Y Coordinate)
#<Z_Coord> = #3 (Z Coordinate)
#<Safe_Z> = #4 (=0 Safe Z height)
#<Y_StepBack> = #5 (= 5 Step back from edge along Y)
#<Bore_depth> = #6 (=20 Depth)
#<FeedRate> = #7 (=300 Feedrate mm/min)
#<ToolNumber> = #8 (=1 Tool Number)
#<Peck> = #9 (=6 Peck Increment)
#<X_Park> = #10 (=0 X Park)
#<Y_Park> = #11 (=0 Y Park)

;set global parameters
;#<_remain_depth> = #<Bore_depth>
;#<_temp_depth> = 0

T#<ToolNumber> M6
G43 T#<ToolNumber>

#<remain_depth> = #<Bore_depth>
#<temp_depth> = 0

S100 M3 F#<FeedRate>

G0 Z#<Safe_Z>
G0 X#<X_Coord> Y[#<Y_Coord> - #<Y_StepBack>]
G0 Z#<Z_Coord>

o<y100> while [#<remain_depth>]
    o<y1100> if [#<remain_depth> GT #<Peck>]
      #<temp_depth> = [#<temp_depth> + #<Peck>]
      G1 Y[#<Y_Coord> + #<temp_depth>]
      G1 Y#<Y_Coord>
      #<remain_depth> = [#<remain_depth> - #<Peck>]
     o<y1100> else
        #<remain_depth> = 0
        G1 Y[#<Y_Coord> + #<Bore_depth>]
        G1 Y[#<Y_Coord> - #<Y_StepBack>]
    o<y1100> endif
o<y100> endwhile

G0 Z#<Safe_Z>

o<drill1> endsub

[code]Here is the error message:

[code][code][code][code]Near line 57 of
/home/cnc/linuxcnc/nc_files/0.auto.ngc:
57:duplicate O-word label: 'o<001y1100>
while [#<remain_depth>]' - defined in line 52

[code][code][code][code]Here is the 0.auto.ngc file that was generated by ngcgui:

[code][code][code][code][code][code][code][code](pyngcgui: FEATURE 210904:14.53.47)
(pyngcgui: files: </home/cnc/linuxcnc/nc_files/ngcgui_lib/utilitysubs/mm_std.ngc,/home/cnc/linuxcnc/nc_files/drill1.ngc,>;)
(pyngcgui: feature line added) #<_feature:> = 0
(pyngcgui: remaining_features line added)  #<_remaining_features:> = 0
(pyngcgui: preamble file: /home/cnc/linuxcnc/nc_files/ngcgui_lib/utilitysubs/mm_std.ngc)
g17 (xy plane)
g21 (mm)
g40 (cancel cutter radius compensation)
g49 (cancel tool lengthoffset)
g90 (absolute distance mode)
g94 (units/min feedrate)
g54 (Coordinate system 1 default)
#<tol>  = 0.001
g64 p#<tol> (path control stop)
(Positional parameters for /home/cnc/linuxcnc/nc_files/drill1.ngc)
        #1 = 50
        #2 = 15
        #3 = 9
        #4 = 0
        #5 = 5
        #6 = 20
        #7 = 300
        #8 = 1
        #9 = 6
        #10 = 0
        #11 = 0
(expanded file: /home/cnc/linuxcnc/nc_files/drill1.ngc)
            (info: Drilling bottom edge with horizontal spindle)
            #<X_Coord> = #1 (X Coordinate)
            #<Y_Coord> = #2 (Y Coordinate)
            #<Z_Coord> = #3 (Z Coordinate)
            #<Safe_Z> = #4 (=0 Safe Z height)
            #<Y_StepBack> = #5 (= 5 Step back from edge along Y)
            #<Bore_depth> = #6 (=20 Depth)
            #<FeedRate> = #7 (=300 Feedrate mm/min)
            #<ToolNumber> = #8 (=1 Tool Number)
            #<Peck> = #9 (=6 Peck Increment)
            #<X_Park> = #10 (=0 X Park)
            #<Y_Park> = #11 (=0 Y Park)
            ;set global parameters
            ;#<_remain_depth> = #<Bore_depth>
            ;#<_temp_depth> = 0
            T#<ToolNumber> M6
            G43 T#<ToolNumber>
            #<remain_depth> = #<Bore_depth>
            #<temp_depth> = 0
            S100 M3 F#<FeedRate>
            G0 Z#<Safe_Z>
            G0 X#<X_Coord> Y[#<Y_Coord> - #<Y_StepBack>]
            G0 Z#<Z_Coord>
 o<001y100>  while [#<remain_depth>]
o<001y1100>  while [#<remain_depth>]
                  #<temp_depth> = [#<temp_depth> + #<Peck>]
                  G1 Y[#<Y_Coord> + #<temp_depth>]
                  G1 Y#<Y_Coord>
                  #<remain_depth> = [#<remain_depth> - #<Peck>]
o<001y1100>  while [#<remain_depth>]
                    #<remain_depth> = 0
                    G1 Y[#<Y_Coord> + #<Bore_depth>]
                    G1 Y[#<Y_Coord> - #<Y_StepBack>]
o<001y1100>  while [#<remain_depth>]
 o<001y100>  endwhile
            G0 Z#<Safe_Z>
(pyngcgui: m2 line added) m2 (g54 activated)