Compilare: user.c: In function ‘main’: user.c:20:3: warning: implicit declaration of function ‘malloc’ [-Wimplicit-function-declaration] val = malloc(sizeof(*val) * 1000000000); ^ user.c:20:9: warning: incompatible implicit declaration of built-in function ‘malloc’ [enabled by default] val = malloc(sizeof(*val) * 1000000000); ^