From 21625e573036b6af90e71046d817fd7c74fa1f2f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kr=C3=B6ning?= <mkroening@posteo.net>
Date: Thu, 2 Jun 2022 00:16:00 +0200
Subject: [PATCH] Session object: Set OS/ABI

This adapts LLVM's behavior of MCELFObjectTargetWriter::getOSABI [1].

[1]: https://github.com/llvm/llvm-project/blob/8c8a2679a20f621994fa904bcfc68775e7345edc/llvm/include/llvm/MC/MCELFObjectWriter.h#L72-L86
---
 Cargo.lock                                      | 15 ++++++++++++++-
 compiler/rustc_codegen_ssa/Cargo.toml           |  2 +-
 compiler/rustc_codegen_ssa/src/back/metadata.rs | 10 +++++++++-
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index c066d1b0a5b..35819572fb9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1688,6 +1688,7 @@ version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8c21d40587b92fa6a6c6e3c1bdbf87d75511db5672f9c93175574b3a00df1758"
 dependencies = [
+ "ahash",
  "compiler_builtins",
  "rustc-std-workspace-alloc",
  "rustc-std-workspace-core",
@@ -2539,6 +2540,18 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "object"
+version = "0.29.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "21158b2c33aa6d4561f1c0a6ea283ca92bc54802a93b263e910746d679a7eb53"
+dependencies = [
+ "crc32fast",
+ "hashbrown 0.12.0",
+ "indexmap",
+ "memchr",
+]
+
 [[package]]
 name = "odht"
 version = "0.3.1"
@@ -3664,7 +3677,7 @@ dependencies = [
  "itertools",
  "jobserver",
  "libc",
- "object 0.28.4",
+ "object 0.29.0",
  "pathdiff",
  "regex",
  "rustc_apfloat",
diff --git a/compiler/rustc_codegen_ssa/Cargo.toml b/compiler/rustc_codegen_ssa/Cargo.toml
index 93b10a07e44..8a3464286a4 100644
--- a/compiler/rustc_codegen_ssa/Cargo.toml
+++ b/compiler/rustc_codegen_ssa/Cargo.toml
@@ -41,6 +41,6 @@ rustc_target = { path = "../rustc_target" }
 rustc_session = { path = "../rustc_session" }
 
 [dependencies.object]
-version = "0.28.4"
+version = "0.29.0"
 default-features = false
 features = ["read_core", "elf", "macho", "pe", "unaligned", "archive", "write"]
diff --git a/compiler/rustc_codegen_ssa/src/back/metadata.rs b/compiler/rustc_codegen_ssa/src/back/metadata.rs
index 4c330c5906a..3dd607adee5 100644
--- a/compiler/rustc_codegen_ssa/src/back/metadata.rs
+++ b/compiler/rustc_codegen_ssa/src/back/metadata.rs
@@ -171,7 +171,15 @@ pub(crate) fn create_object_file(sess: &Session) -> Option<write::Object<'static
         }
         _ => 0,
     };
-    file.flags = FileFlags::Elf { e_flags };
+    // adapted from LLVM's `MCELFObjectTargetWriter::getOSABI`
+    let os_abi = match sess.target.options.os.as_ref() {
+        "hermit" => elf::ELFOSABI_STANDALONE,
+        "freebsd" => elf::ELFOSABI_FREEBSD,
+        "solaris" => elf::ELFOSABI_SOLARIS,
+        _ => elf::ELFOSABI_NONE,
+    };
+    let abi_version = 0;
+    file.flags = FileFlags::Elf { os_abi, abi_version, e_flags };
     Some(file)
 }