Compilare: user.c: In function ‘main’: user.c:196:10: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_result [-Wunused-result] fgets(expresie, 100001, in); ^ user.c: In function ‘postfix’: user.c:101:33: warning: ‘o’ may be used uninitialized in this function [-Wmaybe-uninitialized] push_c(front,rear,0,o); ^ user.c: In function ‘calcul’: user.c:190:5: warning: ‘stack’ may be used uninitialized in this function [-Wmaybe-uninitialized] return stack->val; ^ user.c:170:20: warning: ‘opd1’ may be used uninitialized in this function [-Wmaybe-uninitialized] rez=opd1+opd2; ^ user.c:37:13: warning: ‘rez’ may be used uninitialized in this function [-Wmaybe-uninitialized] nou->val=c; ^ user.c:156:9: note: ‘rez’ was declared here int rez; ^