fix argv handling

tests/c/argv.c

@@ -0,0 +1,9 @@
+#include<stdio.h>
+
+int main(int argc, char* argv[]) {
+    char *self = argv[0];
+    char first = self[0];
+    if (first != '/') {
+        return 1;
+    }
+}

tests/c/malloc.c

@@ -0,0 +1,8 @@
+#include<stdlib.h>
+
+int main(void) {
+    char *alloc = (char*) malloc(10);
+    *alloc = 1;
+    *(alloc + 9) = 2;
+    free(alloc);
+}