rust/compiler/rustc_target/src/spec/base/wasm.rs, branch try-perf

Enable `limit_rdylib_exports` on wasm targets

2025-09-19T20:16:38+00:00

This commit updates the target specification of wasm targets to set the `limit_rdylib_exports` value to `true` like it is on other native platforms. This was originally not implemented long ago as `wasm-ld` didn't have options for symbol exports, but since then it's grown a `--export` flag and such to control this. A custom case is needed in the linker implementation to handle wasm targets as `wasm-ld` doesn't support linker scripts used on other targets, but other than that the implementation is straightforward. The goal of this commit is enable building dynamic libraries on `wasm32-wasip2` which don't export every single symbol in the Rust standard library. Currently, without otherwise control over symbol visibility, all symbols end up being exported which generates excessively large binaries because `--gc-sections` ends up doing nothing as it's all exported anyway.

Adds binary_format to rustc target specs

2025-02-17T15:02:12+00:00

Reformat using the new identifier sorting from rustfmt

2024-09-22T23:11:29+00:00

Add `warn(unreachable_pub)` to `rustc_target`.

2024-09-02T22:49:54+00:00

Remove `default_hidden_visibility: false` from wasm targets

2024-04-16T19:41:44+00:00

To the best of my ability I believe that this is no longer necessary. I don't fully recall why this was first added but I believe it had to do with symbols all being exported by default and this was required to undo that. Regardless nowadays the default output of rustc seems suitable so it seems best to keep wasm in line with other targets.

Remove --fatal-warnings on wasm targets

2024-01-23T19:10:17+00:00

These were added with good intentions, but a recent change in LLVM 18 emits a warning while examining .rmeta sections in .rlib files. Since this flag is a nice-to-have and users can update their LLVM linker independently of rustc's LLVM version, we can just omit the flag.

target: move base specs to spec/base

2023-11-08T06:15:26+00:00

Signed-off-by: David Wood