search

melexis / mlx90640-library

MLX90640 library functions
Apache License 2.0
241 stars 192 forks source link

warning: comparison is always false due to limited range of data type #98

Open birkler opened 2 years ago

birkler commented 2 years ago

E.g. gainEE is declared int8_t so it cannot hold values more than 127.

./mlx90640-library/functions/MLX90640_API.cpp: In function ‘void ExtractGainParameters(uint16_t*, paramsMLX90640*)’:
./mlx90640-library/functions/MLX90640_API.cpp:863:15: warning: comparison is always false due to limited range of data type [-Wtype-limits]
  863 |     if(gainEE > 32767)
      |        ~~~~~~~^~~~~~~
./mlx90640-library/functions/MLX90640_API.cpp: In function ‘void ExtractOffsetParameters(uint16_t*, paramsMLX90640*)’:
./mlx90640-library/functions/MLX90640_API.cpp:1067:19: warning: comparison is always false due to limited range of data type [-Wtype-limits]
 1067 |     if (offsetRef > 32767)
      |         ~~~~~~~~~~^~~~~~~
./mlx90640-library/functions/MLX90640_API.cpp: In function ‘void ExtractKtaPixelParameters(uint16_t*, paramsMLX90640*)’:
./mlx90640-library/functions/MLX90640_API.cpp:1139:17: warning: comparison is always false due to limited range of data type [-Wtype-limits]
 1139 |     if (KtaRoCo > 127)
      |         ~~~~~~~~^~~~~
./mlx90640-library/functions/MLX90640_API.cpp:1146:17: warning: comparison is always false due to limited range of data type [-Wtype-limits]
 1146 |     if (KtaReCo > 127)
      |         ~~~~~~~~^~~~~
./mlx90640-library/functions/MLX90640_API.cpp:1153:17: warning: comparison is always false due to limited range of data type [-Wtype-limits]
 1153 |     if (KtaRoCe > 127)
      |         ~~~~~~~~^~~~~
./mlx90640-library/functions/MLX90640_API.cpp:1160:17: warning: comparison is always false due to limited range of data type [-Wtype-limits]
 1160 |     if (KtaReCe > 127)
      |         ~~~~~~~~^~~~~
aksdfauytv commented 2 years ago

Also, the expression inside doesn't make sense: KtaRoCo = KtaRoCo - 256; will do nothing, since KtaRoCo is only 8 bits wide. Same goes for all the others. Did you mean to invert the value? KtaRoCo = 256 - KtaRoCo; Since KtaRoCo (and others) are signed, you can just do if (KtaRoCo < 0)