make error

mkdir -p build gcc src/glove.c -o build/glove -lm -pthread -Ofast -march=native -funroll-loops -Wall -Wextra -Wpedantic src/glove.c:1:1: warning: C++ style comments are not allowed in ISO C90 [enabled by default] // GloVe: Global Vectors for Word Representation ^ src/glove.c:1:1: warning: (this will be reported only once per input file) [enabled by default] src/glove.c:57:6: warning: ISO C90 does not support ‘long long’ [-Wlong-long] long long num_lines, *lines_per_thread, vocab_size;

how to make the code ？