curves SEGV running ASAN tests

[jaromil]

Running #153 reports this:

{
 "name":"Curves",
 "type":"filter",
 "color_model":"rgba8888",
 "num_params":"16"
},
 "parameters":[
  {"name":"Channel","type":"double","explanation":"Channel to adjust (0 = red, 0.1 = green, 0.2 = blue, 0.3 = alpha, 0.4 = luma, 0.5 = rgb, 0.6 = hue, 0.7 = saturation)"},
  {"name":"Show curves","type":"bool","explanation":"Draw curve graph on output image"},
  {"name":"Graph position","type":"double","explanation":"Output image corner where curve graph will be drawn (0.1 = TOP,LEFT; 0.2 = TOP,RIGHT; 0.3 = BOTTOM,LEFT; 0.4 = BOTTOM, RIGHT)"},
  {"name":"Curve point number","type":"double","explanation":"Number of points to use to build curve (/10 to fit [0,1] parameter range). Minimum 2 (0.2), Maximum 5 (0.5). Not relevant for Bézier spline."},
  {"name":"Luma formula","type":"bool","explanation":"Use Rec. 601 (false) or Rec. 709 (true)"},
  {"name":"Bézier spline","type":"string","explanation":"Use cubic Bézier spline. Has to be a sorted list of points in the format 'handle1x;handle1y#pointx;pointy#handle2x;handle2y'(pointx = in, pointy = out). Points are separated by a '|'.The values can have 'double' precision. x, y for points should be in the range 0-1. x,y for handles might also be out of this range."},
  {"name":"Point 1 input value","type":"double","explanation":"Point 1 input value"},
  {"name":"Point 1 output value","type":"double","explanation":"Point 1 output value"},
  {"name":"Point 2 input value","type":"double","explanation":"Point 2 input value"},
  {"name":"Point 2 output value","type":"double","explanation":"Point 2 output value"},
  {"name":"Point 3 input value","type":"double","explanation":"Point 3 input value"},
  {"name":"Point 3 output value","type":"double","explanation":"Point 3 output value"},
  {"name":"Point 4 input value","type":"double","explanation":"Point 4 input value"},
  {"name":"Point 4 output value","type":"double","explanation":"Point 4 output value"},
  {"name":"Point 5 input value","type":"double","explanation":"Point 5 input value"},
  {"name":"Point 5 output value","type":"double","explanation":"Point 5 output value"}
 ]
}
AddressSanitizer:DEADLYSIGNAL
=================================================================
==26525==ERROR: AddressSanitizer: SEGV on unknown address (pc 0x7f02020c1568 bp 0x7ffc48a7f270 sp 0x7ffc48a7ea00 T0)
==26525==The signal is caused by a READ memory access.
==26525==Hint: this fault was caused by a dereference of a high value address (see register values below).  Disassemble the provided pc to learn which register was used.
    #0 0x7f02020c1568 in strcmp ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:466
    #1 0x7f0201f0b024 in f0r_set_param_value /home/jrml/devel/frei0r/src/filter/curves/curves.c:340
    #2 0x558aabdcedcd in test_parameters(void*, void (*)(void*, void*, int), void (*)(f0r_param_info*, int), int, int) /home/jrml/devel/frei0r/test/frei0r-run.c:171
    #3 0x558aabdcf8ed in main /home/jrml/devel/frei0r/test/frei0r-run.c:370
    #4 0x7f0201a33ca7  (/lib/x86_64-linux-gnu/libc.so.6+0x29ca7) (BuildId: def5460e3cee00bfee25b429c97bcc4853e5b3a8)
    #5 0x7f0201a33d64 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29d64) (BuildId: def5460e3cee00bfee25b429c97bcc4853e5b3a8)
    #6 0x558aabdce260 in _start (/home/jrml/devel/frei0r/test/frei0r-run+0x3260) (BuildId: a01640d73d2b6b674124aa6fc0fa8fdab427fa36)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:466 in strcmp
==26525==ABORTING