From b76dd8c807c5ad32d2dac603937d6661b4685f59 Mon Sep 17 00:00:00 2001 From: kadmin Date: Tue, 4 Apr 2023 08:41:44 +0000 Subject: [PATCH] Add feature gate --- compiler/rustc_feature/src/active.rs | 2 + compiler/rustc_hir_typeck/src/intrinsicck.rs | 2 +- compiler/rustc_middle/src/ty/layout.rs | 16 ++-- compiler/rustc_span/src/symbol.rs | 1 + tests/ui/const-generics/transmute-fail.rs | 1 + tests/ui/const-generics/transmute-fail.stderr | 20 ++-- tests/ui/const-generics/transmute.rs | 1 + tests/ui/const-generics/transmute_no_gate.rs | 91 +++++++++++++++++++ .../const-generics/transmute_no_gate.stderr | 84 +++++++++++++++++ 9 files changed, 200 insertions(+), 18 deletions(-) create mode 100644 tests/ui/const-generics/transmute_no_gate.rs create mode 100644 tests/ui/const-generics/transmute_no_gate.stderr diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs index b7d280b8751c9..8fb8c9b1883f6 100644 --- a/compiler/rustc_feature/src/active.rs +++ b/compiler/rustc_feature/src/active.rs @@ -516,6 +516,8 @@ declare_features! ( /// Allows dyn upcasting trait objects via supertraits. /// Dyn upcasting is casting, e.g., `dyn Foo -> dyn Bar` where `Foo: Bar`. (active, trait_upcasting, "1.56.0", Some(65991), None), + /// Allows for transmuting between arrays with sizes that contain generic consts. + (active, transmute_generic_consts, "CURRENT_RUSTC_VERSION", Some(109929), None), /// Allows #[repr(transparent)] on unions (RFC 2645). (active, transparent_unions, "1.37.0", Some(60405), None), /// Allows inconsistent bounds in where clauses. diff --git a/compiler/rustc_hir_typeck/src/intrinsicck.rs b/compiler/rustc_hir_typeck/src/intrinsicck.rs index eedab9fa1b0a1..bb1d3bb7a308e 100644 --- a/compiler/rustc_hir_typeck/src/intrinsicck.rs +++ b/compiler/rustc_hir_typeck/src/intrinsicck.rs @@ -88,7 +88,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { if let Some(size) = size.try_eval_target_usize(tcx, self.param_env) { format!("{size} bytes") } else { - format!("generic size") + format!("generic size {size}") } } Err(LayoutError::Unknown(bad)) => { diff --git a/compiler/rustc_middle/src/ty/layout.rs b/compiler/rustc_middle/src/ty/layout.rs index 2a057e71eac45..f52e785cd0ae7 100644 --- a/compiler/rustc_middle/src/ty/layout.rs +++ b/compiler/rustc_middle/src/ty/layout.rs @@ -332,7 +332,9 @@ impl<'tcx> SizeSkeleton<'tcx> { ), } } - ty::Array(inner, len) if len.ty() == tcx.types.usize => { + ty::Array(inner, len) + if len.ty() == tcx.types.usize && tcx.features().transmute_generic_consts => + { match SizeSkeleton::compute(inner, tcx, param_env)? { // This may succeed because the multiplication of two types may overflow // but a single size of a nested array will not. @@ -483,17 +485,17 @@ fn mul_sorted_consts<'tcx>( } let mut k = 1; let mut overflow = false; - for _ in done.drain_filter(|c| { + done.retain(|c| { let Some(c) = c.try_eval_target_usize(tcx, param_env) else { - return false; + return true; }; let Some(next) = c.checked_mul(k) else { overflow = true; - return true; + return false; }; - k *= next; - true - }) {} + k = next; + false + }); if overflow { return None; } diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 0ed9935314506..bc2e9cbb8afe9 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -1493,6 +1493,7 @@ symbols! { trait_alias, trait_upcasting, transmute, + transmute_generic_consts, transmute_opts, transmute_trait, transparent, diff --git a/tests/ui/const-generics/transmute-fail.rs b/tests/ui/const-generics/transmute-fail.rs index 490e4de9aac71..d7bf1b47fb5a7 100644 --- a/tests/ui/const-generics/transmute-fail.rs +++ b/tests/ui/const-generics/transmute-fail.rs @@ -1,3 +1,4 @@ +#![feature(transmute_generic_consts)] #![feature(generic_const_exprs)] #![allow(incomplete_features)] diff --git a/tests/ui/const-generics/transmute-fail.stderr b/tests/ui/const-generics/transmute-fail.stderr index bf6a3b61dbb27..41b098135e81e 100644 --- a/tests/ui/const-generics/transmute-fail.stderr +++ b/tests/ui/const-generics/transmute-fail.stderr @@ -1,14 +1,14 @@ error[E0512]: cannot transmute between types of different sizes, or dependently-sized types - --> $DIR/transmute-fail.rs:6:5 + --> $DIR/transmute-fail.rs:7:5 | LL | std::mem::transmute(v) | ^^^^^^^^^^^^^^^^^^^ | - = note: source type: `[[u32; H+1]; W]` (generic size) - = note: target type: `[[u32; W+1]; H]` (generic size) + = note: source type: `[[u32; H+1]; W]` (generic size [const expr]) + = note: target type: `[[u32; W+1]; H]` (generic size [const expr]) error[E0512]: cannot transmute between types of different sizes, or dependently-sized types - --> $DIR/transmute-fail.rs:15:5 + --> $DIR/transmute-fail.rs:16:5 | LL | std::mem::transmute(v) | ^^^^^^^^^^^^^^^^^^^ @@ -17,28 +17,28 @@ LL | std::mem::transmute(v) = note: target type: `[[u32; W]; H]` (size can vary because of [u32; W]) error[E0308]: mismatched types - --> $DIR/transmute-fail.rs:11:53 + --> $DIR/transmute-fail.rs:12:53 | LL | fn bar(v: [[u32; H]; W]) -> [[u32; W]; H] { | ^ expected `usize`, found `bool` error[E0308]: mismatched types - --> $DIR/transmute-fail.rs:11:67 + --> $DIR/transmute-fail.rs:12:67 | LL | fn bar(v: [[u32; H]; W]) -> [[u32; W]; H] { | ^ expected `usize`, found `bool` error[E0512]: cannot transmute between types of different sizes, or dependently-sized types - --> $DIR/transmute-fail.rs:22:5 + --> $DIR/transmute-fail.rs:23:5 | LL | std::mem::transmute(v) | ^^^^^^^^^^^^^^^^^^^ | - = note: source type: `[[u32; H]; W]` (generic size) - = note: target type: `[u32; W * H * H]` (generic size) + = note: source type: `[[u32; H]; W]` (generic size [const expr]) + = note: target type: `[u32; W * H * H]` (generic size [const expr]) error[E0512]: cannot transmute between types of different sizes, or dependently-sized types - --> $DIR/transmute-fail.rs:29:5 + --> $DIR/transmute-fail.rs:30:5 | LL | std::mem::transmute(v) | ^^^^^^^^^^^^^^^^^^^ diff --git a/tests/ui/const-generics/transmute.rs b/tests/ui/const-generics/transmute.rs index 9571b9157049e..30560a95b5e16 100644 --- a/tests/ui/const-generics/transmute.rs +++ b/tests/ui/const-generics/transmute.rs @@ -1,5 +1,6 @@ // run-pass #![feature(generic_const_exprs)] +#![feature(transmute_generic_consts)] #![allow(incomplete_features)] fn transpose(v: [[u32;H]; W]) -> [[u32; W]; H] { diff --git a/tests/ui/const-generics/transmute_no_gate.rs b/tests/ui/const-generics/transmute_no_gate.rs new file mode 100644 index 0000000000000..e1ac44390a5f8 --- /dev/null +++ b/tests/ui/const-generics/transmute_no_gate.rs @@ -0,0 +1,91 @@ +// gate-test-transmute_generic_consts +#![feature(generic_const_exprs)] +#![allow(incomplete_features)] + +fn transpose(v: [[u32;H]; W]) -> [[u32; W]; H] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn ident(v: [[u32; H]; W]) -> [[u32; H]; W] { + unsafe { + std::mem::transmute(v) + } +} + +fn flatten(v: [[u32; H]; W]) -> [u32; W * H] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn coagulate(v: [u32; H*W]) -> [[u32; W];H] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn flatten_3d( + v: [[[u32; D]; H]; W] +) -> [u32; D * W * H] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn flatten_somewhat( + v: [[[u32; D]; H]; W] +) -> [[u32; D * W]; H] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn known_size(v: [u16; L]) -> [u8; L * 2] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn condense_bytes(v: [u8; L * 2]) -> [u16; L] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn singleton_each(v: [u8; L]) -> [[u8;1]; L] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn transpose_with_const( + v: [[u32; 2 * H]; W + W] +) -> [[u32; W + W]; 2 * H] { + unsafe { + std::mem::transmute(v) + //~^ ERROR cannot transmute + } +} + +fn main() { + let _ = transpose([[0; 8]; 16]); + let _ = transpose_with_const::<8,4>([[0; 8]; 16]); + let _ = ident([[0; 8]; 16]); + let _ = flatten([[0; 13]; 5]); + let _: [[_; 5]; 13] = coagulate([0; 65]); + let _ = flatten_3d([[[0; 3]; 13]; 5]); + let _ = flatten_somewhat([[[0; 3]; 13]; 5]); + let _ = known_size([16; 13]); + let _: [u16; 5] = condense_bytes([16u8; 10]); + let _ = singleton_each([16; 10]); +} diff --git a/tests/ui/const-generics/transmute_no_gate.stderr b/tests/ui/const-generics/transmute_no_gate.stderr new file mode 100644 index 0000000000000..9c271b34849c0 --- /dev/null +++ b/tests/ui/const-generics/transmute_no_gate.stderr @@ -0,0 +1,84 @@ +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:7:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[[u32; H]; W]` (this type does not have a fixed size) + = note: target type: `[[u32; W]; H]` (this type does not have a fixed size) + +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:20:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[[u32; H]; W]` (this type does not have a fixed size) + = note: target type: `[u32; W * H]` (this type does not have a fixed size) + +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:27:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[u32; H*W]` (this type does not have a fixed size) + = note: target type: `[[u32; W]; H]` (this type does not have a fixed size) + +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:36:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[[[u32; D]; H]; W]` (this type does not have a fixed size) + = note: target type: `[u32; D * W * H]` (this type does not have a fixed size) + +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:45:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[[[u32; D]; H]; W]` (this type does not have a fixed size) + = note: target type: `[[u32; D * W]; H]` (this type does not have a fixed size) + +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:52:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[u16; L]` (this type does not have a fixed size) + = note: target type: `[u8; L * 2]` (this type does not have a fixed size) + +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:59:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[u8; L * 2]` (this type does not have a fixed size) + = note: target type: `[u16; L]` (this type does not have a fixed size) + +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:66:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[u8; L]` (this type does not have a fixed size) + = note: target type: `[[u8; 1]; L]` (this type does not have a fixed size) + +error[E0512]: cannot transmute between types of different sizes, or dependently-sized types + --> $DIR/transmute_no_gate.rs:75:5 + | +LL | std::mem::transmute(v) + | ^^^^^^^^^^^^^^^^^^^ + | + = note: source type: `[[u32; 2 * H]; W + W]` (this type does not have a fixed size) + = note: target type: `[[u32; W + W]; 2 * H]` (this type does not have a fixed size) + +error: aborting due to 9 previous errors + +For more information about this error, try `rustc --explain E0512`.