diff --git a/compiler/rustc_abi/src/extern_abi.rs b/compiler/rustc_abi/src/extern_abi.rs index c29db522511d8..543c2f8ab12cf 100644 --- a/compiler/rustc_abi/src/extern_abi.rs +++ b/compiler/rustc_abi/src/extern_abi.rs @@ -195,7 +195,6 @@ impl ExternAbi { // * C and Cdecl obviously support varargs. // * C can be based on Aapcs, SysV64 or Win64, so they must support varargs. // * EfiApi is based on Win64 or C, so it also supports it. - // * System falls back to C for functions with varargs. // // * Stdcall does not, because it would be impossible for the callee to clean // up the arguments. (callee doesn't know how many arguments are there) @@ -204,7 +203,6 @@ impl ExternAbi { match self { Self::C { .. } | Self::Cdecl { .. } - | Self::System { .. } | Self::Aapcs { .. } | Self::Win64 { .. } | Self::SysV64 { .. } diff --git a/compiler/rustc_feature/src/unstable.rs b/compiler/rustc_feature/src/unstable.rs index b3fdafe36e611..1eb799961013f 100644 --- a/compiler/rustc_feature/src/unstable.rs +++ b/compiler/rustc_feature/src/unstable.rs @@ -487,9 +487,11 @@ declare_features! ( (unstable, exhaustive_patterns, "1.13.0", Some(51085)), /// Allows explicit tail calls via `become` expression. (incomplete, explicit_tail_calls, "1.72.0", Some(112788)), - /// Allows using `efiapi`, `sysv64` and `win64` as calling convention + /// Allows using `aapcs`, `efiapi`, `sysv64` and `win64` as calling conventions /// for functions with varargs. (unstable, extended_varargs_abi_support, "1.65.0", Some(100189)), + /// Allows using `system` as a calling convention with varargs. + (unstable, extern_system_varargs, "CURRENT_RUSTC_VERSION", Some(136946)), /// Allows defining `extern type`s. (unstable, extern_types, "1.23.0", Some(43467)), /// Allow using 128-bit (quad precision) floating point numbers. diff --git a/compiler/rustc_hir_analysis/src/lib.rs b/compiler/rustc_hir_analysis/src/lib.rs index 323b912ca18ad..8a529e9c686e0 100644 --- a/compiler/rustc_hir_analysis/src/lib.rs +++ b/compiler/rustc_hir_analysis/src/lib.rs @@ -122,28 +122,42 @@ fn require_c_abi_if_c_variadic( const UNSTABLE_EXPLAIN: &str = "using calling conventions other than `C` or `cdecl` for varargs functions is unstable"; + // ABIs which can stably use varargs if !decl.c_variadic || matches!(abi, ExternAbi::C { .. } | ExternAbi::Cdecl { .. }) { return; } + // ABIs with feature-gated stability let extended_abi_support = tcx.features().extended_varargs_abi_support(); - let conventions = match (extended_abi_support, abi.supports_varargs()) { - // User enabled additional ABI support for varargs and function ABI matches those ones. - (true, true) => return, + let extern_system_varargs = tcx.features().extern_system_varargs(); - // Using this ABI would be ok, if the feature for additional ABI support was enabled. - // Return CONVENTIONS_STABLE, because we want the other error to look the same. - (false, true) => { - feature_err(&tcx.sess, sym::extended_varargs_abi_support, span, UNSTABLE_EXPLAIN) - .emit(); - CONVENTIONS_STABLE - } - - (false, false) => CONVENTIONS_STABLE, - (true, false) => CONVENTIONS_UNSTABLE, + // If the feature gate has been enabled, we can stop here + if extern_system_varargs && let ExternAbi::System { .. } = abi { + return; + }; + if extended_abi_support && abi.supports_varargs() { + return; }; - tcx.dcx().emit_err(errors::VariadicFunctionCompatibleConvention { span, conventions }); + // Looks like we need to pick an error to emit. + // Is there any feature which we could have enabled to make this work? + match abi { + ExternAbi::System { .. } => { + feature_err(&tcx.sess, sym::extern_system_varargs, span, UNSTABLE_EXPLAIN) + } + abi if abi.supports_varargs() => { + feature_err(&tcx.sess, sym::extended_varargs_abi_support, span, UNSTABLE_EXPLAIN) + } + _ => tcx.dcx().create_err(errors::VariadicFunctionCompatibleConvention { + span, + conventions: if tcx.sess.opts.unstable_features.is_nightly_build() { + CONVENTIONS_UNSTABLE + } else { + CONVENTIONS_STABLE + }, + }), + } + .emit(); } pub fn provide(providers: &mut Providers) { diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 11dc2edf98604..538f4e8fdcb93 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -881,6 +881,7 @@ symbols! { extern_crate_self, extern_in_paths, extern_prelude, + extern_system_varargs, extern_types, external, external_doc, diff --git a/tests/ui/c-variadic/feature-gate-extended_varargs_abi_support.rs b/tests/ui/c-variadic/feature-gate-extended_varargs_abi_support.rs index d47a8e085fd3a..58370bff2200e 100644 --- a/tests/ui/c-variadic/feature-gate-extended_varargs_abi_support.rs +++ b/tests/ui/c-variadic/feature-gate-extended_varargs_abi_support.rs @@ -1,18 +1,15 @@ //@ only-x86_64 fn efiapi(f: extern "efiapi" fn(usize, ...)) { - //~^ ERROR: C-variadic function must have a compatible calling convention, like `C` or `cdecl` - //~^^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable + //~^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable f(22, 44); } fn sysv(f: extern "sysv64" fn(usize, ...)) { - //~^ ERROR: C-variadic function must have a compatible calling convention, like `C` or `cdecl` - //~^^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable + //~^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable f(22, 44); } fn win(f: extern "win64" fn(usize, ...)) { - //~^ ERROR: C-variadic function must have a compatible calling convention, like `C` or `cdecl` - //~^^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable + //~^ ERROR: using calling conventions other than `C` or `cdecl` for varargs functions is unstable f(22, 44); } diff --git a/tests/ui/c-variadic/feature-gate-extended_varargs_abi_support.stderr b/tests/ui/c-variadic/feature-gate-extended_varargs_abi_support.stderr index 41be378424543..9565575dc4279 100644 --- a/tests/ui/c-variadic/feature-gate-extended_varargs_abi_support.stderr +++ b/tests/ui/c-variadic/feature-gate-extended_varargs_abi_support.stderr @@ -8,14 +8,8 @@ LL | fn efiapi(f: extern "efiapi" fn(usize, ...)) { = help: add `#![feature(extended_varargs_abi_support)]` to the crate attributes to enable = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date -error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl` - --> $DIR/feature-gate-extended_varargs_abi_support.rs:3:14 - | -LL | fn efiapi(f: extern "efiapi" fn(usize, ...)) { - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention - error[E0658]: using calling conventions other than `C` or `cdecl` for varargs functions is unstable - --> $DIR/feature-gate-extended_varargs_abi_support.rs:8:12 + --> $DIR/feature-gate-extended_varargs_abi_support.rs:7:12 | LL | fn sysv(f: extern "sysv64" fn(usize, ...)) { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -24,14 +18,8 @@ LL | fn sysv(f: extern "sysv64" fn(usize, ...)) { = help: add `#![feature(extended_varargs_abi_support)]` to the crate attributes to enable = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date -error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl` - --> $DIR/feature-gate-extended_varargs_abi_support.rs:8:12 - | -LL | fn sysv(f: extern "sysv64" fn(usize, ...)) { - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention - error[E0658]: using calling conventions other than `C` or `cdecl` for varargs functions is unstable - --> $DIR/feature-gate-extended_varargs_abi_support.rs:13:11 + --> $DIR/feature-gate-extended_varargs_abi_support.rs:11:11 | LL | fn win(f: extern "win64" fn(usize, ...)) { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -40,13 +28,6 @@ LL | fn win(f: extern "win64" fn(usize, ...)) { = help: add `#![feature(extended_varargs_abi_support)]` to the crate attributes to enable = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date -error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl` - --> $DIR/feature-gate-extended_varargs_abi_support.rs:13:11 - | -LL | fn win(f: extern "win64" fn(usize, ...)) { - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C-variadic function must have a compatible calling convention - -error: aborting due to 6 previous errors +error: aborting due to 3 previous errors -Some errors have detailed explanations: E0045, E0658. -For more information about an error, try `rustc --explain E0045`. +For more information about this error, try `rustc --explain E0658`. diff --git a/tests/ui/c-variadic/variadic-ffi-1.stderr b/tests/ui/c-variadic/variadic-ffi-1.stderr index dd8c7e93c4efe..061eae9729e2e 100644 --- a/tests/ui/c-variadic/variadic-ffi-1.stderr +++ b/tests/ui/c-variadic/variadic-ffi-1.stderr @@ -1,4 +1,4 @@ -error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl` +error[E0045]: C-variadic function must have a compatible calling convention, like `C`, `cdecl`, `system`, `aapcs`, `win64`, `sysv64` or `efiapi` --> $DIR/variadic-ffi-1.rs:9:5 | LL | fn printf(_: *const u8, ...); diff --git a/tests/ui/c-variadic/variadic-ffi-2.rs b/tests/ui/c-variadic/variadic-ffi-2.rs index bafb7e2b20cc7..99f83f22d17c0 100644 --- a/tests/ui/c-variadic/variadic-ffi-2.rs +++ b/tests/ui/c-variadic/variadic-ffi-2.rs @@ -8,9 +8,6 @@ fn baz(f: extern "stdcall" fn(usize, ...)) { f(22, 44); } -fn system(f: extern "system" fn(usize, ...)) { - f(22, 44); -} #[cfg(target_arch = "x86_64")] fn sysv(f: extern "sysv64" fn(usize, ...)) { f(22, 44); diff --git a/tests/ui/cmse-nonsecure/cmse-nonsecure-call/generics.rs b/tests/ui/cmse-nonsecure/cmse-nonsecure-call/generics.rs index 9e0ffa75c2296..31782b05105f6 100644 --- a/tests/ui/cmse-nonsecure/cmse-nonsecure-call/generics.rs +++ b/tests/ui/cmse-nonsecure/cmse-nonsecure-call/generics.rs @@ -39,4 +39,4 @@ type WithTransparentTraitObject = //~^ ERROR return value of `"C-cmse-nonsecure-call"` function too large to pass via registers [E0798] type WithVarArgs = extern "C-cmse-nonsecure-call" fn(u32, ...); -//~^ ERROR C-variadic function must have a compatible calling convention, like `C` or `cdecl` [E0045] +//~^ ERROR C-variadic function must have a compatible calling convention, like `C` diff --git a/tests/ui/cmse-nonsecure/cmse-nonsecure-call/generics.stderr b/tests/ui/cmse-nonsecure/cmse-nonsecure-call/generics.stderr index f0d5f648f4c65..0560f0eec1c02 100644 --- a/tests/ui/cmse-nonsecure/cmse-nonsecure-call/generics.stderr +++ b/tests/ui/cmse-nonsecure/cmse-nonsecure-call/generics.stderr @@ -69,7 +69,7 @@ LL | extern "C-cmse-nonsecure-call" fn(WrapperTransparent) -> WrapperTranspa = note: functions with the `"C-cmse-nonsecure-call"` ABI must pass their result via the available return registers = note: the result must either be a (transparently wrapped) i64, u64 or f64, or be at most 4 bytes in size -error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl` +error[E0045]: C-variadic function must have a compatible calling convention, like `C`, `cdecl`, `system`, `aapcs`, `win64`, `sysv64` or `efiapi` --> $DIR/generics.rs:41:20 | LL | type WithVarArgs = extern "C-cmse-nonsecure-call" fn(u32, ...); diff --git a/tests/ui/error-codes/E0045.stderr b/tests/ui/error-codes/E0045.stderr index 25b2f2654da15..b8ee31a40495a 100644 --- a/tests/ui/error-codes/E0045.stderr +++ b/tests/ui/error-codes/E0045.stderr @@ -1,4 +1,4 @@ -error[E0045]: C-variadic function must have a compatible calling convention, like `C` or `cdecl` +error[E0045]: C-variadic function must have a compatible calling convention, like `C`, `cdecl`, `system`, `aapcs`, `win64`, `sysv64` or `efiapi` --> $DIR/E0045.rs:1:17 | LL | extern "Rust" { fn foo(x: u8, ...); } diff --git a/tests/ui/feature-gates/feature-gate-extern_system_varargs.rs b/tests/ui/feature-gates/feature-gate-extern_system_varargs.rs new file mode 100644 index 0000000000000..f5cfbe72ca8db --- /dev/null +++ b/tests/ui/feature-gates/feature-gate-extern_system_varargs.rs @@ -0,0 +1,7 @@ +fn system(f: extern "system" fn(usize, ...)) { + //~^ ERROR using calling conventions other than `C` or `cdecl` for varargs functions is unstable + + f(22, 44); +} + +fn main() {} diff --git a/tests/ui/feature-gates/feature-gate-extern_system_varargs.stderr b/tests/ui/feature-gates/feature-gate-extern_system_varargs.stderr new file mode 100644 index 0000000000000..f3206b25264e0 --- /dev/null +++ b/tests/ui/feature-gates/feature-gate-extern_system_varargs.stderr @@ -0,0 +1,13 @@ +error[E0658]: using calling conventions other than `C` or `cdecl` for varargs functions is unstable + --> $DIR/feature-gate-extern_system_varargs.rs:1:14 + | +LL | fn system(f: extern "system" fn(usize, ...)) { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: see issue #136946 for more information + = help: add `#![feature(extern_system_varargs)]` to the crate attributes to enable + = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0658`.