diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_middle/src/ty/mod.rs | 9 | ||||
| -rw-r--r-- | compiler/rustc_session/src/options.rs | 2 |
2 files changed, 10 insertions, 1 deletions
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs index d0d2a46fc4c..529e8478371 100644 --- a/compiler/rustc_middle/src/ty/mod.rs +++ b/compiler/rustc_middle/src/ty/mod.rs @@ -1640,7 +1640,14 @@ impl ReprOptions { // Generate a deterministically-derived seed from the item's path hash // to allow for cross-crate compilation to actually work - let field_shuffle_seed = tcx.def_path_hash(did).0.to_smaller_hash(); + let mut field_shuffle_seed = tcx.def_path_hash(did).0.to_smaller_hash(); + + // If the user defined a custom seed for layout randomization, xor the item's + // path hash with the user defined seed, this will allowing determinism while + // still allowing users to further randomize layout generation for e.g. fuzzing + if let Some(user_seed) = tcx.sess.opts.debugging_opts.layout_seed { + field_shuffle_seed ^= user_seed; + } for attr in tcx.get_attrs(did).iter() { for r in attr::find_repr_attrs(&tcx.sess, attr) { diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs index bd7b1639613..32fabb6be4b 100644 --- a/compiler/rustc_session/src/options.rs +++ b/compiler/rustc_session/src/options.rs @@ -1321,6 +1321,8 @@ options! { "print some statistics about the query system (default: no)"), randomize_layout: bool = (false, parse_bool, [TRACKED], "randomize the layout of types (default: no)"), + layout_seed: Option<u64> = (None, parse_opt_number, [TRACKED], + "seed layout randomization"), relax_elf_relocations: Option<bool> = (None, parse_opt_bool, [TRACKED], "whether ELF relocations can be relaxed"), relro_level: Option<RelroLevel> = (None, parse_relro_level, [TRACKED], |