@programminginc - страница 607

Roxifλsz 🇱🇹

Are you certain that the exact line you posted is causing the segfault?

BinaryByter

according to the VSC debugger (gdb) yep

Roxifλsz 🇱🇹

according to the VSC debugger (gdb) yep

Try running valgrind memcheck on the executable, it should tell you if something wasn't allocated or something like that

BinaryByter

let's do that

Ludovic 'Archivist'

why the fuck does this line fucking produce a segfault?

Because the vector is not initialized maybe

BinaryByter

Because the vector is not initialized maybe

it is

BinaryByter

infact, I use it many times before pushing back

BinaryByter

struct tape { int estimated_size = 0; std::vector<char> tape_vector; int read_position = 0; tape(int es_size) : estimated_size(es_size), tape_vector(estimated_size, 0) { } ~tape() { } inline void write_cell() { std::cout << tape_vector[read_position]; } inline void input_cell() { std::cin >> tape_vector[read_position]; } inline void increase_cell_position() { read_position++; if (read_position >= tape_vector.size()) tape_vector.push_back(0); } inline void decrease_cell_position() { read_position--; } inline void increment_cell() { tape_vector[read_position]++; } inline void decrement_cell() { tape_vector[read_position]--; } };

olli

struct tape { int estimated_size = 0; std::vector<char> tape_vector; int read_position = 0; tape(int es_size) : estimated_size(es_size), tape_vector(estimated_size, 0) { } ~tape() { } inline void write_cell() { std::cout << tape_vector[read_position]; } inline void input_cell() { std::cin >> tape_vector[read_position]; } inline void increase_cell_position() { read_position++; if (read_position >= tape_vector.size()) tape_vector.push_back(0); } inline void decrease_cell_position() { read_position--; } inline void increment_cell() { tape_vector[read_position]++; } inline void decrement_cell() { tape_vector[read_position]--; } };

How do you use it? Maybe you are calling input_cell with an out of bounds index. The next reallocation might fail. Does valgrind report any access violation?

olli

Using clang++ should link against libstdc++ as g++ does

BinaryByter

How do you use it? Maybe you are calling input_cell with an out of bounds index. The next reallocation might fail. Does valgrind report any access violation?

valgrind mainly complains because of uninitialized variables

olli

valgrind mainly complains because of uninitialized variables

Then you should initialize them, and what are the minor complaints?

BinaryByter

Then you should initialize them, and what are the minor complaints?

Oh right

BinaryByter