...

src/runtime/entry.s

@@ -1,12 +0,0 @@
-.intel_syntax noprefix
-
-.equ SYS_EXIT, 60
-
-.text
-.globl _start
-_start:
-    mov rdi, rsp
-    call main
-    mov rdi, rax
-    mov rax, SYS_EXIT
-    syscall

src/runtime/runtime.c

@@ -1,17 +1,49 @@
 #include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/syscall.h>
+#include <syscall.h>
+#include <unistd.h>
 
 #define NUB_PANIC_ERROR_CODE 101
 
-uint64_t nub_cstring_length() { return 0; }
+uint64_t nub_cstring_length(char* string)
+{
+    return strlen(string);
+}
 
-uint64_t nub_string_length() {}
+uint64_t nub_string_length()
+{
+    return 0;
+}
 
-void nub_memcpy() {}
+void nub_memcpy(void* source, void* destination, uint64_t length)
+{
+    memcpy(destination, source, length);
+}
 
-void nub_memset() {}
+void nub_memset(void* destination, int value, uint64_t count)
+{
+    memset(destination, value, count);
+}
 
-void nub_panic() {}
+void nub_panic_array_oob()
+{
+    puts("Array out of bounds");
+    exit(NUB_PANIC_ERROR_CODE);
+}
 
-void nub_panic_array_oob() {}
+void nub_panic_oom()
+{
+    puts("Out of memory");
+    exit(NUB_PANIC_ERROR_CODE);
+}
 
-void nub_panic_oom() {}
+extern int64_t main();
+
+void _start()
+{
+    int64_t exit_code = main();
+    exit(exit_code);
+}