Auto merge of #117919 - daxpedda:wasm-c-abi, r=wesleywiser

Introduce perma-unstable `wasm-c-abi` flag

Now that `wasm-bindgen` v0.2.88 supports the spec-compliant C ABI, the idea is to switch to that in a future version of Rust. In the meantime it would be good to let people test and play around with it.

This PR introduces a new perma-unstable `-Zwasm-c-abi` compiler flag, which switches to the new spec-compliant C ABI when targeting `wasm32-unknown-unknown`.

Alternatively, we could also stabilize this and then deprecate it when we switch. I will leave this to the Rust maintainers to decide.

This is a companion PR to #117918, but they could be merged independently.
MCP: https://github.com/rust-lang/compiler-team/issues/703
Tracking issue: https://github.com/rust-lang/rust/issues/122532

1 files changed, 4 insertions, 1 deletions

diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs
index e563728c893..9d53f0799ea 100644
--- a/compiler/rustc_interface/src/tests.rs
+++ b/compiler/rustc_interface/src/tests.rs
@@ -19,7 +19,9 @@ use rustc_span::edition::{Edition, DEFAULT_EDITION};
 use rustc_span::source_map::{RealFileLoader, SourceMapInputs};
 use rustc_span::symbol::sym;
 use rustc_span::{FileName, SourceFileHashAlgorithm};
-use rustc_target::spec::{CodeModel, LinkerFlavorCli, MergeFunctions, PanicStrategy, RelocModel};
+use rustc_target::spec::{
+    CodeModel, LinkerFlavorCli, MergeFunctions, PanicStrategy, RelocModel, WasmCAbi,
+};
 use rustc_target::spec::{RelroLevel, SanitizerSet, SplitDebuginfo, StackProtector, TlsModel};
 use std::collections::{BTreeMap, BTreeSet};
 use std::num::NonZero;
@@ -851,6 +853,7 @@ fn test_unstable_options_tracking_hash() {
     tracked!(verify_llvm_ir, true);
     tracked!(virtual_function_elimination, true);
     tracked!(wasi_exec_model, Some(WasiExecModel::Reactor));
+    tracked!(wasm_c_abi, WasmCAbi::Spec);
     // tidy-alphabetical-end
 
     macro_rules! tracked_no_crate_hash {