a much more simplified version of push_back with reallocf instead of memcpy as it is faster (no copying just resizing the vector (entire point of vector))

tests/crash_9b_test.c

@@ -0,0 +1,107 @@
+#include <mach/mach.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+typedef struct
+{
+	char* arr;
+	size_t size;
+	size_t capacity;
+} Vec8_t;
+
+#define CAPACITY 1024
+
+Vec8_t
+create(const Vec8_t* input)
+{
+	Vec8_t vec = { .arr = NULL, .size = 0, .capacity = CAPACITY };
+	if (input == NULL)
+	{
+		vec.arr = calloc(vec.capacity, sizeof(char));
+		return vec;
+	}
+	if (input->size > 0)
+	{
+		vec.size = input->size + 1;
+	}
+	vec.arr = calloc(vec.capacity, sizeof(char));
+	return vec;
+}
+
+void
+delete(Vec8_t* vec)
+{
+	if (vec->arr != NULL)
+	{
+		free(vec->arr);
+		vec->arr = NULL;
+	}
+	vec->size = 0;
+	vec->capacity = 0;
+}
+
+Vec8_t
+add_back(Vec8_t* vec, const char val)
+{
+	if (vec->size >= vec->capacity)
+	{
+		vec->capacity = 2 * vec->capacity;
+		char* new_arr =
+		    reallocf(vec->arr, vec->capacity * sizeof(char));
+		if (new_arr == NULL)
+		{
+			return *vec;
+		}
+		vec->arr = new_arr;
+	}
+	vec->arr[vec->size] = val;
+	vec->size++;
+	return *vec;
+}
+
+vm_size_t
+get_physical_mem()
+{
+	struct task_basic_info info;
+	mach_msg_type_number_t count = TASK_BASIC_INFO_COUNT;
+	task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)&info,
+		  &count);
+	return info.resident_size;
+}
+
+int
+main()
+{
+	printf("=== PROGRESSIVE TEST: 1K -> 10K -> 100K -> 1M -> 10M -> 100M -> 1B ===\n\n");
+	
+	size_t targets[] = {1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000};
+	int num_tests = 7;
+	
+	for (int t = 0; t < num_tests; t++) {
+		size_t target = targets[t];
+		printf("\n=== TEST %d: %zu elements ===\n", t+1, target);
+		
+		Vec8_t vec = create(NULL);
+		size_t start_cap = vec.capacity;
+		
+		for (size_t i = 0; i < target; i++) {
+			vec = add_back(&vec, 'x');
+			
+			if (vec.arr == NULL) {
+				printf("CRASHED at %zu elements!\n", i);
+				return 1;
+			}
+		}
+		
+		printf("SUCCESS: %zu elements, capacity %zu\n", vec.size, vec.capacity);
+		printf("Memory: %.2f MB\n", get_physical_mem() / 1024.0 / 1024.0);
+		
+		delete(&vec);
+	}
+	
+	printf("\n=== ALL TESTS PASSED ===\n");
+	printf("Final memory: %.2f MB\n", get_physical_mem() / 1024.0 / 1024.0);
+	
+	return 0;
+}