Hi,
The user is encountering memory corruption (e.g., scores turning into garbage values like -1110238145) and a segmentation fault in their Raspberry Pi 5 project using SquareLine Studio. These issues are likely caused by:
-
Memory Management Errors
- Invalid pointer usage (e.g., accessing freed memory).
- Widgets/labels being created or freed incorrectly.
-
Format Specifier Mismatches
- Using
%d for non-integer variables (or vice versa) in lv_label_set_text_fmt().
-
Uninitialized Variables
- Variables like
score or current_hole might not be initialized, leading to garbage values.
-
Thread Safety Issues
- Asynchronous updates to UI elements without proper synchronization (e.g., mutexes).
Solution Steps
1. Verify Format Specifiers
Ensure the format specifiers in lv_label_set_text_fmt() match the variable types. For example:
int score = 0;
lv_label_set_text_fmt(label_score, "Score: %d", score); // Use %d for integers
If using float, use %f:
float sensor_value = 4.5;
lv_label_set_text_fmt(label_sensor, "Value: %.2f", sensor_value);
2. Initialize Variables
Always initialize variables to avoid garbage values:
int current_hole = 1; // Start at 1, not 0
int score = 0;
3. Check Widget Lifecycle
- Ensure widgets are created once and not recreated unnecessarily.
- Avoid freeing labels/widgets that are still in use.
4. Use Debugging Tools
Run the program with valgrind to detect memory leaks or invalid accesses:
valgrind ./your_program
Look for errors like “Invalid read/write” or “Use of uninitialized value.”
5. Add Debug Logs
Print variable values before updating the UI to catch inconsistencies:
printf("DEBUG: Score=%d, Hole=%d\n", score, current_hole); // Check if values make sense
lv_label_set_text_fmt(label_score, "Score: %d", score);
6. Review Thread Safety
If using multiple threads to update the UI:
- Use mutexes to protect shared resources (e.g., labels).
- Avoid updating UI elements from interrupts or callbacks without synchronization.
7. Check Sensor Inputs
Ensure sensor values are within expected ranges before using them:
if (sensor_value < 0 || sensor_value > 10) {
printf("ERROR: Invalid sensor value: %d\n", sensor_value);
return;
}
Example Fix
// Initialize variables
int score = 0;
int current_hole = 1;
// Update labels safely
void update_score_label() {
printf("DEBUG: Updating score=%d\n", score); // Debug log
lv_label_set_text_fmt(label_score, "Score: %d", score); // Correct format
}
// Handle sensor input
void on_sensor_detection(int sensor_value) {
if (sensor_value < 0 || sensor_value > 4) { // Validate input
printf("ERROR: Invalid sensor value: %d\n", sensor_value);
return;
}
score += sensor_value;
update_score_label();
}
Final Notes
- If the issue persists, share the relevant code snippets (e.g., label updates, sensor handling) for further analysis.
- Simplify the project temporarily (e.g., test with 1 screen) to isolate the problem.
