Fix rebase and fix test

In CI, the cross-lang-lto-clang passed on x86_64 but not on aarch64.
I don’t have a good way to debug this, but with some local changes
(my clang to cross-compiling to aarch64 uses different target features,
so nothing gets inlined by default; and I wasn’t able to link a rust std
for aarch64), I think I found the culprit.

With fat lto on aarch64, the inline(never) rust function gets inlined.
This is the same behavior as with linking a C library into a Rust
binary, just that it’s different between aarch64 and x86 (fat lto on x86
inlines the noinline C function into the Rust binary but it does
not inline the inline(never) Rust function into the C binary).

Author: Flakebi

src/tools/run-make-support/src/lib.rs

@@ -63,7 +63,7 @@ pub use crate::external_deps::clang::{Clang, clang};
 pub use crate::external_deps::htmldocck::htmldocck;
 pub use crate::external_deps::llvm::{
     self, LlvmAr, LlvmBcanalyzer, LlvmDis, LlvmDwarfdump, LlvmFilecheck, LlvmNm, LlvmObjcopy,
-    LlvmObjdump, LlvmProfdata, LlvmReadobj, llvm_ar, llvm_bcanalyzer, llvm_dis, llvm_dwarfdump,
+    LlvmObjdump, LlvmProfdata, LlvmReadobj, llvm_ar, llvm_as, llvm_bcanalyzer, llvm_dis, llvm_dwarfdump,
     llvm_filecheck, llvm_nm, llvm_objcopy, llvm_objdump, llvm_profdata, llvm_readobj,
 };
 pub use crate::external_deps::python::python_command;

tests/run-make/cross-lang-lto-clang/rmake.rs

@@ -35,6 +35,7 @@ fn main() {
 fn test_lto(fat_lto: bool) {
     let lto = if fat_lto { "fat" } else { "thin" };
     let clang_lto = if fat_lto { "full" } else { "thin" };
+    println!("Running {lto} lto");
 
     rustc()
         .lto(lto)
@@ -52,20 +53,25 @@ fn test_lto(fat_lto: bool) {
         .input("cmain.c")
         .arg("-O3")
         .run();
+
+    let dump = llvm_objdump().disassemble().input("cmain").run();
     // Make sure we don't find a call instruction to the function we expect to
     // always be inlined.
-    llvm_objdump()
-        .disassemble()
-        .input("cmain")
-        .run()
-        .assert_stdout_not_contains_regex(RUST_ALWAYS_INLINED_PATTERN);
+    dump.assert_stdout_not_contains_regex(RUST_ALWAYS_INLINED_PATTERN);
     // As a sanity check, make sure we do find a call instruction to a
     // non-inlined function
-    llvm_objdump()
-        .disassemble()
-        .input("cmain")
-        .run()
-        .assert_stdout_contains_regex(RUST_NEVER_INLINED_PATTERN);
+    #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
+    dump.assert_stdout_contains_regex(RUST_NEVER_INLINED_PATTERN);
+    #[cfg(any(target_arch = "aarch64", target_arch = "arm"))]
+    {
+        if !fat_lto {
+            dump.assert_stdout_contains_regex(RUST_NEVER_INLINED_PATTERN);
+        } else {
+            // fat lto inlines this anyway
+            dump.assert_stdout_not_contains_regex(RUST_NEVER_INLINED_PATTERN);
+        }
+    }
+
     clang().input("clib.c").lto(clang_lto).arg("-c").out_exe("clib.o").arg("-O2").run();
     llvm_ar().obj_to_ar().output_input(static_lib_name("xyz"), "clib.o").run();
     rustc()
@@ -77,13 +83,9 @@ fn test_lto(fat_lto: bool) {
         .input("main.rs")
         .output("rsmain")
         .run();
-    llvm_objdump()
-        .disassemble()
-        .input("rsmain")
-        .run()
-        .assert_stdout_not_contains_regex(C_ALWAYS_INLINED_PATTERN);
 
     let dump = llvm_objdump().disassemble().input("rsmain").run();
+    dump.assert_stdout_not_contains_regex(C_ALWAYS_INLINED_PATTERN);
     if !fat_lto {
         dump.assert_stdout_contains_regex(C_NEVER_INLINED_PATTERN);
     } else {

tests/run-make/fat-then-thin-lto/lib.rs

@@ -1,8 +1,13 @@
+#![allow(internal_features)]
 #![feature(no_core, lang_items)]
 #![no_core]
 #![crate_type = "rlib"]
 
+#[lang = "pointee_sized"]
+trait PointeeSized {}
+#[lang = "meta_sized"]
+trait MetaSized: PointeeSized {}
 #[lang = "sized"]
-trait Sized {}
+trait Sized: MetaSized {}
 
 pub fn foo() {}

tests/run-make/linker-plugin-lto-fat/main.rs

@@ -1,9 +1,14 @@
+#![allow(internal_features)]
 #![feature(no_core, lang_items)]
 #![no_core]
 #![crate_type = "cdylib"]
 
+#[lang = "pointee_sized"]
+trait PointeeSized {}
+#[lang = "meta_sized"]
+trait MetaSized: PointeeSized {}
 #[lang = "sized"]
-trait Sized {}
+trait Sized: MetaSized {}
 
 extern "C" {
     fn ir_callee();

tests/run-make/linker-plugin-lto-fat/rmake.rs

@@ -16,7 +16,8 @@ fn main() {
         .lto("fat")
         .linker_plugin_lto("on")
         .link_arg("ir.bc")
-        .arg("-Zlinker-features=+lld")
+        .arg("-Zunstable-options")
+        .arg("-Clinker-features=+lld")
         .run();
 
     llvm_objdump()