Download libserialport library.
git clone git://sigrok.org/libserialport
For build code use build script or build files manually.
Example:
export C_INCLUDE_PATH=<path/to/libserialport>
export LIBRARY_PATH=<path/to/libserialport/.libs>
gcc -static -Wall -O3 -o <output_filename> <file.c> -lserialport