added missing -lm

sqrt() -> sqrtf()

SP5WWP/lib/Makefile

@@ -3,7 +3,7 @@ INC     = -I .
 TARGET  = libm17.so
 
 CFLAGS  = $(INC) -fPIC
-LDFLAGS = -shared
+LDFLAGS = -shared -lm
 SRCS    = $(wildcard *.c) $(wildcard */*.c)
 OBJS    = $(SRCS:.c=.o)
 

SP5WWP/lib/math/math.c

@@ -44,7 +44,7 @@ float eucl_norm(const float* in1, const int8_t* in2, const uint8_t n)
         tmp += powf(in1[i]-(float)in2[i], 2.0f);
     }
 
-    return sqrt(tmp);
+    return sqrtf(tmp);
 }
 
 /**