The compilation failed, so I'll have to take another look at the debug option tomorrow, but at least this reproduces it on my test machine with 7.8.116:
/* No attempt has been made to reduce this further. */ void main() { mkdir("test");
string foo = "x"*17; string bar = "y"*18; for(int i=0; i<68; i++) mkdir( "test/"+ (i + foo)[0..16] ); for(int i=0; i<164; i++) mkdir( "test/"+ (i + bar)[0..17] );
if( sizeof(get_dir("test")) != 68+164) werror("Fail!\n"); }