Auto merge of #118568 - DianQK:no-builtins-symbols, r=pnkfelix

Avoid adding builtin functions to `symbols.o`

We found performance regressions in #113923. The problem seems to be that `--gc-sections` does not remove these symbols. I tested that lld removes these symbols, but ld and gold do not.

I found that `used` adds symbols to `symbols.o` at https://github.com/rust-lang/rust/blob/3e202ead604be31f4c1a5798a296953d3159da7e/compiler/rustc_codegen_ssa/src/back/linker.rs#L1786-L1791.
The PR removes builtin functions.

Note that under LTO, ld still preserves these symbols. (lld will still remove them.)

The first commit also fixes #118559. But I think the second commit also makes sense.

Author: bors

src/bin/miri.rs

@@ -165,6 +165,7 @@ impl rustc_driver::Callbacks for MiriBeRustCompilerCalls {
                                     level: SymbolExportLevel::C,
                                     kind: SymbolExportKind::Text,
                                     used: false,
+                                    used_compiler: false,
                                 },
                             ))
                         }),