rust-lang/rust
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Make lto and linker-plugin-lto work the same for compiler_builtins

Browse Source 
Fix #142284 by ensuring that `#![no_builtins]` crates can still emit bitcode
when proper (i.e., non-rustc) LTO (i.e., -Clinker-plugin-lto) is used.
This commit is contained in:
Matthew Maurer
2025-06-10 23:37:05 +00:00
committed by Ramon de C Valle
parent d9dba3a554
commit cf8753e4f9
2 changed files with 23 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
compiler/rustc_codegen_ssa/src/back/write.rs
View File

@@ -143,23 +143,12 @@ impl ModuleConfig {
let emit_obj = if !should_emit_obj {
EmitObj::None
} else if sess.target.obj_is_bitcode
|| (sess.opts.cg.linker_plugin_lto.enabled() && !no_builtins)
{
} else if sess.target.obj_is_bitcode || sess.opts.cg.linker_plugin_lto.enabled() {
// This case is selected if the target uses objects as bitcode, or
// if linker plugin LTO is enabled. In the linker plugin LTO case
// the assumption is that the final link-step will read the bitcode
// and convert it to object code. This may be done by either the
// native linker or rustc itself.
//
// Note, however, that the linker-plugin-lto requested here is
// explicitly ignored for `#![no_builtins]` crates. These crates are
// specifically ignored by rustc's LTO passes and wouldn't work if
// loaded into the linker. These crates define symbols that LLVM
// lowers intrinsics to, and these symbol dependencies aren't known
// until after codegen. As a result any crate marked
// `#![no_builtins]` is assumed to not participate in LTO and
// instead goes on to generate object code.
EmitObj::Bitcode
} else if need_bitcode_in_object(tcx) {
EmitObj::ObjectCode(BitcodeSection::Full)