From 2c44bb13c63a785ba197247661da94a0aa1dd5ce Mon Sep 17 00:00:00 2001
From: bjorn3 <17426603+bjorn3@users.noreply.github.com>
Date: Wed, 11 Feb 2026 11:58:51 +0000
Subject: [PATCH] Support serializing CodegenContext

---
 compiler/rustc_codegen_ssa/src/back/write.rs |  8 +++++---
 compiler/rustc_session/src/config.rs         | 14 +++++++-------
 compiler/rustc_target/src/spec/mod.rs        |  2 +-
 3 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index 082dd2cb41cc..87a043fbdf24 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -23,6 +23,7 @@ use rustc_hir::find_attr;
 use rustc_incremental::{
     copy_cgu_workproduct_to_incr_comp_cache_dir, in_incr_comp_dir, in_incr_comp_dir_sess,
 };
+use rustc_macros::{Decodable, Encodable};
 use rustc_metadata::fs::copy_to_stdout;
 use rustc_middle::bug;
 use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
@@ -50,7 +51,7 @@ use crate::{
 const PRE_LTO_BC_EXT: &str = "pre-lto.bc";
 
 /// What kind of object file to emit.
-#[derive(Clone, Copy, PartialEq)]
+#[derive(Clone, Copy, PartialEq, Encodable, Decodable)]
 pub enum EmitObj {
     // No object file.
     None,
@@ -64,7 +65,7 @@ pub enum EmitObj {
 }
 
 /// What kind of llvm bitcode section to embed in an object file.
-#[derive(Clone, Copy, PartialEq)]
+#[derive(Clone, Copy, PartialEq, Encodable, Decodable)]
 pub enum BitcodeSection {
     // No bitcode section.
     None,
@@ -74,6 +75,7 @@ pub enum BitcodeSection {
 }
 
 /// Module-specific configuration for `optimize_and_codegen`.
+#[derive(Encodable, Decodable)]
 pub struct ModuleConfig {
     /// Names of additional optimization passes to run.
     pub passes: Vec<String>,
@@ -319,7 +321,7 @@ pub type TargetMachineFactoryFn<B> = Arc<
 >;
 
 /// Additional resources used by optimize_and_codegen (not module specific)
-#[derive(Clone)]
+#[derive(Clone, Encodable, Decodable)]
 pub struct CodegenContext {
     // Resources needed when running LTO
     pub lto: Lto,
diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index 5e2671ef4ef6..b278a6179fe7 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -88,7 +88,7 @@ pub enum CFProtection {
     Full,
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Hash, HashStable_Generic)]
+#[derive(Clone, Copy, Debug, PartialEq, Hash, HashStable_Generic, Encodable, Decodable)]
 pub enum OptLevel {
     /// `-Copt-level=0`
     No,
@@ -108,7 +108,7 @@ pub enum OptLevel {
 /// and taking other command line options into account.
 ///
 /// Note that linker plugin-based LTO is a different mechanism entirely.
-#[derive(Clone, PartialEq)]
+#[derive(Clone, PartialEq, Encodable, Decodable)]
 pub enum Lto {
     /// Don't do any LTO whatsoever.
     No,
@@ -190,7 +190,7 @@ pub enum CoverageLevel {
 }
 
 // The different settings that the `-Z offload` flag can have.
-#[derive(Clone, PartialEq, Hash, Debug)]
+#[derive(Clone, PartialEq, Hash, Debug, Encodable, Decodable)]
 pub enum Offload {
     /// Entry point for `std::offload`, enables kernel compilation for a gpu device
     Device,
@@ -201,7 +201,7 @@ pub enum Offload {
 }
 
 /// The different settings that the `-Z autodiff` flag can have.
-#[derive(Clone, PartialEq, Hash, Debug)]
+#[derive(Clone, PartialEq, Hash, Debug, Encodable, Decodable)]
 pub enum AutoDiff {
     /// Enable the autodiff opt pipeline
     Enable,
@@ -528,7 +528,7 @@ impl FmtDebug {
     }
 }
 
-#[derive(Clone, PartialEq, Hash, Debug)]
+#[derive(Clone, PartialEq, Hash, Debug, Encodable, Decodable)]
 pub enum SwitchWithOptPath {
     Enabled(Option<PathBuf>),
     Disabled,
@@ -583,7 +583,7 @@ pub enum MirStripDebugInfo {
 /// DWARF provides a mechanism which allows the linker to skip the sections which don't require
 /// link-time relocation - either by putting those sections in DWARF object files, or by keeping
 /// them in the object file in such a way that the linker will skip them.
-#[derive(Clone, Copy, Debug, PartialEq, Hash)]
+#[derive(Clone, Copy, Debug, PartialEq, Hash, Encodable, Decodable)]
 pub enum SplitDwarfKind {
     /// Sections which do not require relocation are written into object file but ignored by the
     /// linker.
@@ -1539,7 +1539,7 @@ pub enum EntryFnType {
 
 pub use rustc_hir::attrs::CrateType;
 
-#[derive(Clone, Hash, Debug, PartialEq, Eq)]
+#[derive(Clone, Hash, Debug, PartialEq, Eq, Encodable, Decodable)]
 pub enum Passes {
     Some(Vec<String>),
     All,
diff --git a/compiler/rustc_target/src/spec/mod.rs b/compiler/rustc_target/src/spec/mod.rs
index 537185f536ab..2d2f15651c43 100644
--- a/compiler/rustc_target/src/spec/mod.rs
+++ b/compiler/rustc_target/src/spec/mod.rs
@@ -1082,7 +1082,7 @@ crate::target_spec_enum! {
 }
 
 crate::target_spec_enum! {
-    #[derive(Default)]
+    #[derive(Default, Encodable, Decodable)]
     pub enum SplitDebuginfo {
         /// Split debug-information is disabled, meaning that on supported platforms
         /// you can find all debug information in the executable itself. This is