# sysctl -w kernel.randomize_va_space=2
$ ./configure && make && ./node test/parallel/test-snapshot-reproducible.js
node:internal/assert/utils:146
throw error;
^
AssertionError [ERR_ASSERTION]: Expected values to be strictly deep-equal:
+ actual - expected
... Skipped lines
[
'#include <cstddef>',
'#include "env.h"',
'#include "node_snapshot_builder.h"',
'#include "v8.h"',
...
'namespace node {',
+ 'static const char v8_snapshot_blob_data[] = {4,0,0,0,1,0,0,0,43,108,-20,-8,-43,-25,-94,-55,49,52,46,54,46,50,48,50,46,51,52,45,110,111,100,101,46,50,49,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 0',
- 'static const char v8_snapshot_blob_data[] = {4,0,0,0,1,0,0,0,-99,103,75,7,-43,-25,-94,-55,49,52,46,54,46,50,48,50,46,51,52,45,110,111,100,101,46,50,49,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 0',
'0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,16,10,23,0,64,8,25,0,72,114,29,0,8,107,30,0,-120,98,31,0,-40,88,32,0,-85,6,-34,-64,-96,9,23,0,-83,24,96,0,0,0,0,86,0,0,0,96,0,0,0,0, // 1',
'0,0,0,0,96,0,0,0,0,0,0,0,0,96,0,0,0,0,-53,1,0,0,96,0,0,0,0,-84,1,0,0,96,0,0,0,0,-64,2,0,0,96,0,0,0,0,0,0,0,0,96,0,0,0,0,-30,0,0,0,11,5,24,98,0,2, // 2',
'5,24,34,1,2,5,24,-30,1,2,5,24,-94,2,2,5,24,98,3,2,5,24,34,4,2,5,24,-30,4,2,5,24,-94,5,2,5,24,98,6,2,5,24,34,7,2,5,24,-30,7,2,5,24,-94,8,2,5,24,98,9,2,1,76,7,101, // 3',
'15,69,64,97,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,64,98,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,64,96,0,0,0,0,0,0,0,0,7,-123,2,64,96,0,0,0, // 4',
'0,8,0,0,0,-127,0,91,64,1,20,83,69,97,0,0,0,0,96,0,0,0,0,0,0,0,1,0,0,0,93,1,20,83,69,97,0,0,0,0,96,0,0,0,0,0,0,0,1,0,0,0,93,1,20,83,69,97,0,0,0,0,96,0, // 5',
...
'26,-87,22,26,-11,27,26,93,28,26,101,28,26,105,34,26,69,37,26,73,37,26,77,37,26,81,37,26,85,37,26,89,37,26,93,37,26,97,37,26,101,37,26,-87,43,26,-83,43,26,-71,43,1,20,86,98,0,0,0,0,3,0,0,0,0, // 42996',
+ '0,0,0,1,0,0,0,0,0,0,0,14,0,0,0,64,91,31,0,6,-71,2,5,24,66,66,4,4,8,95,4,73,33,11,15,0,-3,15,0,8,6,0,0,-3,15,4,96,6,-86,-127,-107,44,127,0,0,24,0,0,0,0,0,0,0,47, // 42997',
+ '0,0,0,0,0,0,0,0,-107,26,0,8,8,0,0,-107,26,4,64,8,-102,-74,95,5,0,0,0,16,0,0,0,0,0,0,0,0,-99,39,0,8,2,0,0,-99,39,4,-64,2,-102,-74,95,5,0,0,0,48,0,0,0,0,0,0,0,51, // 42998',
+ '0,0,0,0,0,0,0,52,0,0,0,0,0,0,0,53,0,0,0,0,0,0,0,54,0,0,0,0,0,0,0,0,-67,49,0,8,7,0,0,-67,49,4,64,7,-102,-74,95,5,0,0,0,16,0,0,0,0,0,0,0,0,-123,56,0,8, // 42999',
+ '9,0,0,-123,56,4,64,9,-101,-74,95,5,0,0,0,16,0,0,0,0,0,0,0,0,-59,79,-128,32,32,0,0,0,0,0,0,0,0,-59,79,-108,32,37,0,0,0,0,0,0,0,0,-59,79,-104,32,38,0,0,0,0,0,0,0,0,-59, // 43000',
+ '79,-100,32,39,0,0,0,0,0,0,0,0,-91,108,0,8,3,0,0,-91,108,4,96,3,-86,-127,-107,44,127,0,0,24,0,0,0,0,0,0,0,43,0,0,0,0,0,0,0,0,-75,108,0,8,0,0,0,-75,108,4,96,0,-102,-74,95,5, // 43001',
+ '0,0,0,24,0,0,0,0,0,0,0,45,0,0,0,0,0,0,0,0,-67,108,0,8,5,0,0,-67,108,4,64,5,114,5,54,-2,85,0,0,16,0,0,0,0,0,0,0,0,-51,108,0,8,1,0,0,-51,108,4,96,1,-102,-74,95,5, // 43002',
- '0,0,0,1,0,0,0,0,0,0,0,14,0,0,0,64,91,31,0,6,-71,2,5,24,66,66,4,4,8,95,4,73,33,11,15,0,-3,15,0,8,6,0,0,-3,15,4,96,6,-86,33,30,70,127,0,0,24,0,0,0,0,0,0,0,47, // 42997',
- '0,0,0,0,0,0,0,0,-107,26,0,8,8,0,0,-107,26,4,64,8,36,-106,100,5,0,0,0,16,0,0,0,0,0,0,0,0,-99,39,0,8,2,0,0,-99,39,4,-64,2,36,-106,100,5,0,0,0,48,0,0,0,0,0,0,0,51, // 42998',
- '0,0,0,0,0,0,0,52,0,0,0,0,0,0,0,53,0,0,0,0,0,0,0,54,0,0,0,0,0,0,0,0,-67,49,0,8,7,0,0,-67,49,4,64,7,36,-106,100,5,0,0,0,16,0,0,0,0,0,0,0,0,-123,56,0,8, // 42999',
- '9,0,0,-123,56,4,64,9,36,-106,100,5,0,0,0,16,0,0,0,0,0,0,0,0,-59,79,-128,32,32,0,0,0,0,0,0,0,0,-59,79,-108,32,37,0,0,0,0,0,0,0,0,-59,79,-104,32,38,0,0,0,0,0,0,0,0,-59, // 43000',
- '79,-100,32,39,0,0,0,0,0,0,0,0,-91,108,0,8,3,0,0,-91,108,4,96,3,-86,33,30,70,127,0,0,24,0,0,0,0,0,0,0,43,0,0,0,0,0,0,0,0,-75,108,0,8,0,0,0,-75,108,4,96,0,36,-106,100,5, // 43001',
- '0,0,0,24,0,0,0,0,0,0,0,45,0,0,0,0,0,0,0,0,-67,108,0,8,5,0,0,-67,108,4,64,5,-52,-33,6,76,86,0,0,16,0,0,0,0,0,0,0,0,-51,108,0,8,1,0,0,-51,108,4,96,1,36,-106,100,5, // 43002',
'0,0,0,24,0,0,0,0,0,0,0,57,0,0,0,0,0,0,0,11,10,10,10,10',
'};',
'static const int v8_snapshot_blob_size = 2752216;',
'static const uint8_t vm_cache_data[] = {171,6,222,192,82,189,255,151,217,50,0,32,97,100,152,163,213,231,162,201,96,21,0,0,0,0,0,0,0,0,0,0,1,36,81,3,109,1,7,196,96,0,0,0,0,151,2,0,0,1,8,7,33,15,4,4,33,3,112,7,181,1,122,0, // 0',
'0,0,0,205,0,0,0,2,4,6,0,179,5,156,36,26,100,22,64,26,76,26,68,26,64,23,220,3,14,0,22,203,2,22,80,26,60,22,112,27,216,3,14,0,22,104,22,203,2,26,124,27,168,9,14,0,22,143,7,26,68,26,76,26, // 1',
at Object.<anonymous> (/node/test/parallel/test-snapshot-reproducible.js:47:8)
at Module._compile (node:internal/modules/cjs/loader:1947:14)
at Object..js (node:internal/modules/cjs/loader:2087:10)
at Module.load (node:internal/modules/cjs/loader:1669:32)
at Module._load (node:internal/modules/cjs/loader:1450:12)
at wrapModuleLoad (node:internal/modules/cjs/loader:260:19)
at Module.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:154:5)
at node:internal/main/run_main_module:33:47 {
generatedMessage: true,
code: 'ERR_ASSERTION',
actual: [ <skipped> ],
expected: [ <skipped> ],
operator: 'deepStrictEqual',
diff: 'simple'
}
Node.js v27.0.0-pre
Reproducible locally with gcc 15.3.0 and 16.1.1.
The byteranges that differ are randomized so the exact bytes are different each time. Everything else seems to be consistent.
Completely disabling ASLR (setting kernel/randomize_va_space to 0) makes the test pass. Conservative ASLR (1) still breaks it.
Not exactly sure when this started (maybe some of v8 upgrades?) nor whether it can be fixed (maybe on v8 side?) nor what else causes this (test passes on CI so i assume there's additional factor to it).
Testing
mainon linux:Reproducible locally with gcc 15.3.0 and 16.1.1.
The byteranges that differ are randomized so the exact bytes are different each time. Everything else seems to be consistent.
Completely disabling ASLR (setting
kernel/randomize_va_spaceto0) makes the test pass. Conservative ASLR (1) still breaks it.Not exactly sure when this started (maybe some of v8 upgrades?) nor whether it can be fixed (maybe on v8 side?) nor what else causes this (test passes on CI so i assume there's additional factor to it).