From 3a5df48021b3d29ca55a712d9677cfe043966c6e Mon Sep 17 00:00:00 2001 From: Rich Kadel Date: Mon, 26 Apr 2021 21:25:30 -0700 Subject: [PATCH] adds feature gating of `no_coverage` at either crate- or function-level --- .../src/deriving/cmp/eq.rs | 11 +++++- compiler/rustc_feature/src/active.rs | 4 +++ compiler/rustc_feature/src/builtin_attrs.rs | 8 ++++- compiler/rustc_typeck/src/collect.rs | 28 ++++++++++++++- library/core/src/cmp.rs | 1 + .../expected_show_coverage.issue-84561.txt | 34 ------------------- .../expected_show_coverage.no_cov_crate.txt | 18 ++++++++++ .../expected_show_coverage.no_cov_func.txt | 19 +++++++++++ .../run-make-fulldeps/coverage/issue-84561.rs | 26 -------------- .../coverage/no_cov_crate.rs | 17 ++++++++++ .../run-make-fulldeps/coverage/no_cov_func.rs | 18 ++++++++++ .../feature-gates/feature-gate-no_coverage.rs | 8 +++++ .../feature-gate-no_coverage.stderr | 13 +++++++ 13 files changed, 142 insertions(+), 63 deletions(-) delete mode 100644 src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.issue-84561.txt create mode 100644 src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.no_cov_crate.txt create mode 100644 src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.no_cov_func.txt delete mode 100644 src/test/run-make-fulldeps/coverage/issue-84561.rs create mode 100644 src/test/run-make-fulldeps/coverage/no_cov_crate.rs create mode 100644 src/test/run-make-fulldeps/coverage/no_cov_func.rs create mode 100644 src/test/ui/feature-gates/feature-gate-no_coverage.rs create mode 100644 src/test/ui/feature-gates/feature-gate-no_coverage.stderr diff --git a/compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs b/compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs index 53e9681b437fb..5a4e7fd9d07b4 100644 --- a/compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs +++ b/compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs @@ -16,10 +16,19 @@ pub fn expand_deriving_eq( push: &mut dyn FnMut(Annotatable), ) { let inline = cx.meta_word(span, sym::inline); + let no_coverage_ident = + rustc_ast::attr::mk_nested_word_item(Ident::new(sym::no_coverage, span)); + let no_coverage_feature = + rustc_ast::attr::mk_list_item(Ident::new(sym::feature, span), vec![no_coverage_ident]); let no_coverage = cx.meta_word(span, sym::no_coverage); let hidden = rustc_ast::attr::mk_nested_word_item(Ident::new(sym::hidden, span)); let doc = rustc_ast::attr::mk_list_item(Ident::new(sym::doc, span), vec![hidden]); - let attrs = vec![cx.attribute(inline), cx.attribute(no_coverage), cx.attribute(doc)]; + let attrs = vec![ + cx.attribute(inline), + cx.attribute(no_coverage_feature), + cx.attribute(no_coverage), + cx.attribute(doc), + ]; let trait_def = TraitDef { span, attributes: Vec::new(), diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs index 7ae7e0094c6d1..d5963d34dfaa5 100644 --- a/compiler/rustc_feature/src/active.rs +++ b/compiler/rustc_feature/src/active.rs @@ -649,6 +649,10 @@ declare_features! ( /// Allows `extern "wasm" fn` (active, wasm_abi, "1.53.0", Some(83788), None), + /// Allows function attribute `#[no_coverage]`, to bypass coverage + /// instrumentation of that function. + (active, no_coverage, "1.53.0", Some(84605), None), + /// Allows trait bounds in `const fn`. (active, const_fn_trait_bound, "1.53.0", Some(57563), None), diff --git a/compiler/rustc_feature/src/builtin_attrs.rs b/compiler/rustc_feature/src/builtin_attrs.rs index b35072933d96d..5474fea9c7857 100644 --- a/compiler/rustc_feature/src/builtin_attrs.rs +++ b/compiler/rustc_feature/src/builtin_attrs.rs @@ -264,7 +264,6 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[ // Code generation: ungated!(inline, AssumedUsed, template!(Word, List: "always|never")), - ungated!(no_coverage, AssumedUsed, template!(Word)), ungated!(cold, AssumedUsed, template!(Word)), ungated!(no_builtins, AssumedUsed, template!(Word)), ungated!(target_feature, AssumedUsed, template!(List: r#"enable = "name""#)), @@ -274,6 +273,13 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[ template!(List: "address, memory, thread"), experimental!(no_sanitize) ), + ungated!( + // Not exclusively gated at the crate level (though crate-level is + // supported). The feature can alternatively be enabled on individual + // functions. + no_coverage, AssumedUsed, + template!(Word), + ), // FIXME: #14408 assume docs are used since rustdoc looks at them. ungated!(doc, AssumedUsed, template!(List: "hidden|inline|...", NameValueStr: "string")), diff --git a/compiler/rustc_typeck/src/collect.rs b/compiler/rustc_typeck/src/collect.rs index 0528f8812f920..190c9d35934f9 100644 --- a/compiler/rustc_typeck/src/collect.rs +++ b/compiler/rustc_typeck/src/collect.rs @@ -2661,6 +2661,8 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, id: DefId) -> CodegenFnAttrs { let mut inline_span = None; let mut link_ordinal_span = None; let mut no_sanitize_span = None; + let mut no_coverage_feature_enabled = false; + let mut no_coverage_attr = None; for attr in attrs.iter() { if tcx.sess.check_name(attr, sym::cold) { codegen_fn_attrs.flags |= CodegenFnAttrFlags::COLD; @@ -2724,8 +2726,15 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, id: DefId) -> CodegenFnAttrs { codegen_fn_attrs.flags |= CodegenFnAttrFlags::NAKED; } else if tcx.sess.check_name(attr, sym::no_mangle) { codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE; + } else if attr.has_name(sym::feature) { + if let Some(list) = attr.meta_item_list() { + if list.iter().any(|nested_meta_item| nested_meta_item.has_name(sym::no_coverage)) { + tcx.sess.mark_attr_used(attr); + no_coverage_feature_enabled = true; + } + } } else if tcx.sess.check_name(attr, sym::no_coverage) { - codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_COVERAGE; + no_coverage_attr = Some(attr); } else if tcx.sess.check_name(attr, sym::rustc_std_internal_symbol) { codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL; } else if tcx.sess.check_name(attr, sym::used) { @@ -2936,6 +2945,23 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, id: DefId) -> CodegenFnAttrs { } } + if let Some(no_coverage_attr) = no_coverage_attr { + if tcx.sess.features_untracked().no_coverage || no_coverage_feature_enabled { + codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_COVERAGE + } else { + let mut err = feature_err( + &tcx.sess.parse_sess, + sym::no_coverage, + no_coverage_attr.span, + "the `#[no_coverage]` attribute is an experimental feature", + ); + if tcx.sess.parse_sess.unstable_features.is_nightly_build() { + err.help("or, alternatively, add `#[feature(no_coverage)]` to the function"); + } + err.emit(); + } + } + codegen_fn_attrs.inline = attrs.iter().fold(InlineAttr::None, |ia, attr| { if !attr.has_name(sym::inline) { return ia; diff --git a/library/core/src/cmp.rs b/library/core/src/cmp.rs index 1f7ae7e3773c4..0a3e5789e8bed 100644 --- a/library/core/src/cmp.rs +++ b/library/core/src/cmp.rs @@ -274,6 +274,7 @@ pub trait Eq: PartialEq { // // This should never be implemented by hand. #[doc(hidden)] + #[cfg_attr(not(bootstrap), feature(no_coverage))] #[cfg_attr(not(bootstrap), no_coverage)] #[inline] #[stable(feature = "rust1", since = "1.0.0")] diff --git a/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.issue-84561.txt b/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.issue-84561.txt deleted file mode 100644 index faafa828817ee..0000000000000 --- a/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.issue-84561.txt +++ /dev/null @@ -1,34 +0,0 @@ - 1| |// FIXME(#84561): function-like macros produce unintuitive coverage results. - 2| |// This test demonstrates some of the problems. - 3| | - 4| 9|#[derive(Debug, PartialEq, Eq)] - ^5 - ------------------ - | ::eq: - | 4| 9|#[derive(Debug, PartialEq, Eq)] - ------------------ - | Unexecuted instantiation: ::ne - ------------------ - 5| |struct Foo(u32); - 6| | - 7| 1|fn main() { - 8| 1| let bar = Foo(1); - 9| 0| assert_eq!(bar, Foo(1)); - 10| 1| let baz = Foo(0); - 11| 0| assert_ne!(baz, Foo(1)); - 12| 1| println!("{:?}", Foo(1)); - 13| 1| println!("{:?}", bar); - 14| 1| println!("{:?}", baz); - 15| | - 16| 1| assert_eq!(Foo(1), Foo(1)); - 17| 1| assert_ne!(Foo(0), Foo(1)); - 18| 0| assert_eq!(Foo(2), Foo(2)); - 19| 1| let bar = Foo(1); - 20| 1| assert_ne!(Foo(0), Foo(3)); - 21| 1| assert_ne!(Foo(0), Foo(4)); - 22| 1| assert_eq!(Foo(3), Foo(3)); - 23| 0| assert_ne!(Foo(0), Foo(5)); - 24| 1| println!("{:?}", bar); - 25| 1| println!("{:?}", Foo(1)); - 26| 1|} - diff --git a/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.no_cov_crate.txt b/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.no_cov_crate.txt new file mode 100644 index 0000000000000..c4a7b0cc7e9f3 --- /dev/null +++ b/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.no_cov_crate.txt @@ -0,0 +1,18 @@ + 1| |// Enables `no_coverage` on the entire crate + 2| |#![feature(no_coverage)] + 3| | + 4| |#[no_coverage] + 5| |fn do_not_add_coverage_1() { + 6| | println!("called but not covered"); + 7| |} + 8| | + 9| |#[no_coverage] + 10| |fn do_not_add_coverage_2() { + 11| | println!("called but not covered"); + 12| |} + 13| | + 14| 1|fn main() { + 15| 1| do_not_add_coverage_1(); + 16| 1| do_not_add_coverage_2(); + 17| 1|} + diff --git a/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.no_cov_func.txt b/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.no_cov_func.txt new file mode 100644 index 0000000000000..16eaf7c858c19 --- /dev/null +++ b/src/test/run-make-fulldeps/coverage-reports/expected_show_coverage.no_cov_func.txt @@ -0,0 +1,19 @@ + 1| |// Enables `no_coverage` on individual functions + 2| | + 3| |#[feature(no_coverage)] + 4| |#[no_coverage] + 5| |fn do_not_add_coverage_1() { + 6| | println!("called but not covered"); + 7| |} + 8| | + 9| |#[no_coverage] + 10| |#[feature(no_coverage)] + 11| |fn do_not_add_coverage_2() { + 12| | println!("called but not covered"); + 13| |} + 14| | + 15| 1|fn main() { + 16| 1| do_not_add_coverage_1(); + 17| 1| do_not_add_coverage_2(); + 18| 1|} + diff --git a/src/test/run-make-fulldeps/coverage/issue-84561.rs b/src/test/run-make-fulldeps/coverage/issue-84561.rs deleted file mode 100644 index dc183685e3d11..0000000000000 --- a/src/test/run-make-fulldeps/coverage/issue-84561.rs +++ /dev/null @@ -1,26 +0,0 @@ -// FIXME(#84561): function-like macros produce unintuitive coverage results. -// This test demonstrates some of the problems. - -#[derive(Debug, PartialEq, Eq)] -struct Foo(u32); - -fn main() { - let bar = Foo(1); - assert_eq!(bar, Foo(1)); - let baz = Foo(0); - assert_ne!(baz, Foo(1)); - println!("{:?}", Foo(1)); - println!("{:?}", bar); - println!("{:?}", baz); - - assert_eq!(Foo(1), Foo(1)); - assert_ne!(Foo(0), Foo(1)); - assert_eq!(Foo(2), Foo(2)); - let bar = Foo(1); - assert_ne!(Foo(0), Foo(3)); - assert_ne!(Foo(0), Foo(4)); - assert_eq!(Foo(3), Foo(3)); - assert_ne!(Foo(0), Foo(5)); - println!("{:?}", bar); - println!("{:?}", Foo(1)); -} diff --git a/src/test/run-make-fulldeps/coverage/no_cov_crate.rs b/src/test/run-make-fulldeps/coverage/no_cov_crate.rs new file mode 100644 index 0000000000000..300570db7e8f7 --- /dev/null +++ b/src/test/run-make-fulldeps/coverage/no_cov_crate.rs @@ -0,0 +1,17 @@ +// Enables `no_coverage` on the entire crate +#![feature(no_coverage)] + +#[no_coverage] +fn do_not_add_coverage_1() { + println!("called but not covered"); +} + +#[no_coverage] +fn do_not_add_coverage_2() { + println!("called but not covered"); +} + +fn main() { + do_not_add_coverage_1(); + do_not_add_coverage_2(); +} diff --git a/src/test/run-make-fulldeps/coverage/no_cov_func.rs b/src/test/run-make-fulldeps/coverage/no_cov_func.rs new file mode 100644 index 0000000000000..e19a2c4a87200 --- /dev/null +++ b/src/test/run-make-fulldeps/coverage/no_cov_func.rs @@ -0,0 +1,18 @@ +// Enables `no_coverage` on individual functions + +#[feature(no_coverage)] +#[no_coverage] +fn do_not_add_coverage_1() { + println!("called but not covered"); +} + +#[no_coverage] +#[feature(no_coverage)] +fn do_not_add_coverage_2() { + println!("called but not covered"); +} + +fn main() { + do_not_add_coverage_1(); + do_not_add_coverage_2(); +} diff --git a/src/test/ui/feature-gates/feature-gate-no_coverage.rs b/src/test/ui/feature-gates/feature-gate-no_coverage.rs new file mode 100644 index 0000000000000..c6b79f9a43171 --- /dev/null +++ b/src/test/ui/feature-gates/feature-gate-no_coverage.rs @@ -0,0 +1,8 @@ +#![crate_type = "lib"] + +#[no_coverage] +#[feature(no_coverage)] // does not have to be enabled before `#[no_coverage]` +fn no_coverage_is_enabled_on_this_function() {} + +#[no_coverage] //~ ERROR the `#[no_coverage]` attribute is an experimental feature +fn requires_feature_no_coverage() {} diff --git a/src/test/ui/feature-gates/feature-gate-no_coverage.stderr b/src/test/ui/feature-gates/feature-gate-no_coverage.stderr new file mode 100644 index 0000000000000..04627be4aaf65 --- /dev/null +++ b/src/test/ui/feature-gates/feature-gate-no_coverage.stderr @@ -0,0 +1,13 @@ +error[E0658]: the `#[no_coverage]` attribute is an experimental feature + --> $DIR/feature-gate-no_coverage.rs:7:1 + | +LL | #[no_coverage] + | ^^^^^^^^^^^^^^ + | + = note: see issue #84605 for more information + = help: add `#![feature(no_coverage)]` to the crate attributes to enable + = help: or, alternatively, add `#[feature(no_coverage)]` to the function + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0658`.