_offc_xfile_struct.nx source

1import "syscalls.nx" 2import "xfile_struct_types.nx" 3import "xfile_struct_writer.nx" 4 5// Minimal repro for T#selfhost-006. 6// 7// xfile_struct_types.nx defines `struct G { id, a, b, c, d, e, f, g }` 8// at offsets 0,8,16,24,32,40,48,56 (8 i64 fields, total 64 bytes). 9// We allocate an array of N entries with stride 80 (matching nxc.nx's 10// Global stride; trailing 16 bytes is padding). 11// 12// xfile_struct_writer.nx writes id=i, a=100+i, b=200+i for entries 0..2. 13// Here in main we read the same slots back via `g.id`, `g.a`, `g.b`. 14// 15// If C anchor's struct field-offset assignment is stable across imports, 16// expected stdout: 17// 0 100 200 18// 1 101 201 19// 2 102 202 20// If T#selfhost-006 root cause is per-file Type divergence, the read 21// values will diverge from the written ones and this minimal program 22// makes the bug 20 lines instead of 6KB. 23 24func print_i64(n: i64) -> i64 { 25 let buf: *u8 = sys_mmap(32) 26 var k: i64 = 0 27 var v: i64 = n 28 if v < 0 { sys_write(1, "-" as *u8, 1); v = 0 - v } 29 if v == 0 { buf[k] = 0x30; k = 1 } 30 while v > 0 { 31 buf[k] = 0x30 + (v - (v / 10) * 10) 32 v = v / 10 33 k = k + 1 34 } 35 var j: i64 = k - 1 36 while j >= 0 { 37 sys_write(1, (((buf as i64) + j) as *u8), 1) 38 j = j - 1 39 } 40 return 0 41} 42 43func main() -> i64 { 44 let region: *u8 = sys_mmap(80 * 4) 45 let base: i64 = region as i64 46 47 // Writer fills slots 0,1,2. 48 xfile_writer_fill(base, 3) 49 50 // Reader: walk slots 0..3 and print id, name_len, len. 51 var i: i64 = 0 52 while i < 3 { 53 let g: *G = (base + i * 80) as *G 54 print_i64(g.id); sys_write(1, " " as *u8, 1) 55 print_i64(g.name_len); sys_write(1, " " as *u8, 1) 56 print_i64(g.len); sys_write(1, "\n" as *u8, 1) 57 i = i + 1 58 } 59 return 0 60}