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|
$DIR/auxiliary/used_crate.rs:
LL| |#![allow(unused_assignments, unused_variables)]
LL| |// Verify that coverage works with optimizations:
LL| |// compile-flags: -C opt-level=3
LL| |
LL| |use std::fmt::Debug;
LL| |
LL| 1|pub fn used_function() {
LL| 1| // Initialize test constants in a way that cannot be determined at compile time, to ensure
LL| 1| // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
LL| 1| // dependent conditions.
LL| 1| let is_true = std::env::args().len() == 1;
LL| 1| let mut countdown = 0;
LL| 1| if is_true {
LL| 1| countdown = 10;
LL| 1| }
^0
LL| 1| use_this_lib_crate();
LL| 1|}
LL| |
LL| 2|pub fn used_only_from_bin_crate_generic_function<T: Debug>(arg: T) {
LL| 2| println!("used_only_from_bin_crate_generic_function with {:?}", arg);
LL| 2|}
------------------
| Unexecuted instantiation: used_crate::used_only_from_bin_crate_generic_function::<_>
------------------
| used_crate::used_only_from_bin_crate_generic_function::<&alloc::vec::Vec<i32>>:
| LL| 1|pub fn used_only_from_bin_crate_generic_function<T: Debug>(arg: T) {
| LL| 1| println!("used_only_from_bin_crate_generic_function with {:?}", arg);
| LL| 1|}
------------------
| used_crate::used_only_from_bin_crate_generic_function::<&str>:
| LL| 1|pub fn used_only_from_bin_crate_generic_function<T: Debug>(arg: T) {
| LL| 1| println!("used_only_from_bin_crate_generic_function with {:?}", arg);
| LL| 1|}
------------------
LL| |// Expect for above function: `Unexecuted instantiation` (see below)
LL| 2|pub fn used_only_from_this_lib_crate_generic_function<T: Debug>(arg: T) {
LL| 2| println!("used_only_from_this_lib_crate_generic_function with {:?}", arg);
LL| 2|}
------------------
| used_crate::used_only_from_this_lib_crate_generic_function::<&str>:
| LL| 1|pub fn used_only_from_this_lib_crate_generic_function<T: Debug>(arg: T) {
| LL| 1| println!("used_only_from_this_lib_crate_generic_function with {:?}", arg);
| LL| 1|}
------------------
| used_crate::used_only_from_this_lib_crate_generic_function::<alloc::vec::Vec<i32>>:
| LL| 1|pub fn used_only_from_this_lib_crate_generic_function<T: Debug>(arg: T) {
| LL| 1| println!("used_only_from_this_lib_crate_generic_function with {:?}", arg);
| LL| 1|}
------------------
LL| |
LL| 2|pub fn used_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
LL| 2| println!("used_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
LL| 2|}
------------------
| used_crate::used_from_bin_crate_and_lib_crate_generic_function::<&str>:
| LL| 1|pub fn used_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
| LL| 1| println!("used_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
| LL| 1|}
------------------
| used_crate::used_from_bin_crate_and_lib_crate_generic_function::<alloc::vec::Vec<i32>>:
| LL| 1|pub fn used_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
| LL| 1| println!("used_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
| LL| 1|}
------------------
LL| |
LL| 2|pub fn used_with_same_type_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
LL| 2| println!("used_with_same_type_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
LL| 2|}
------------------
| used_crate::used_with_same_type_from_bin_crate_and_lib_crate_generic_function::<&str>:
| LL| 1|pub fn used_with_same_type_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
| LL| 1| println!("used_with_same_type_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
| LL| 1|}
------------------
| used_crate::used_with_same_type_from_bin_crate_and_lib_crate_generic_function::<&str>:
| LL| 1|pub fn used_with_same_type_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
| LL| 1| println!("used_with_same_type_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
| LL| 1|}
------------------
LL| |
LL| 0|pub fn unused_generic_function<T: Debug>(arg: T) {
LL| 0| println!("unused_generic_function with {:?}", arg);
LL| 0|}
LL| |
LL| 0|pub fn unused_function() {
LL| 0| let is_true = std::env::args().len() == 1;
LL| 0| let mut countdown = 2;
LL| 0| if !is_true {
LL| 0| countdown = 20;
LL| 0| }
LL| 0|}
LL| |
LL| |#[allow(dead_code)]
LL| 0|fn unused_private_function() {
LL| 0| let is_true = std::env::args().len() == 1;
LL| 0| let mut countdown = 2;
LL| 0| if !is_true {
LL| 0| countdown = 20;
LL| 0| }
LL| 0|}
LL| |
LL| 1|fn use_this_lib_crate() {
LL| 1| used_from_bin_crate_and_lib_crate_generic_function("used from library used_crate.rs");
LL| 1| used_with_same_type_from_bin_crate_and_lib_crate_generic_function(
LL| 1| "used from library used_crate.rs",
LL| 1| );
LL| 1| let some_vec = vec![5, 6, 7, 8];
LL| 1| used_only_from_this_lib_crate_generic_function(some_vec);
LL| 1| used_only_from_this_lib_crate_generic_function("used ONLY from library used_crate.rs");
LL| 1|}
LL| |
LL| |// FIXME(#79651): "Unexecuted instantiation" errors appear in coverage results,
LL| |// for example:
LL| |//
LL| |// | Unexecuted instantiation: used_crate::used_only_from_bin_crate_generic_function::<_>
LL| |//
LL| |// These notices appear when `llvm-cov` shows instantiations. This may be a
LL| |// default option, but it can be suppressed with:
LL| |//
LL| |// ```shell
LL| |// $ `llvm-cov show --show-instantiations=0 ...`
LL| |// ```
LL| |//
LL| |// The notice is triggered because the function is unused by the library itself,
LL| |// and when the library is compiled, a synthetic function is generated, so
LL| |// unused function coverage can be reported. Coverage can be skipped for unused
LL| |// generic functions with:
LL| |//
LL| |// ```shell
LL| |// $ `rustc -Zunstable-options -C instrument-coverage=except-unused-generics ...`
LL| |// ```
LL| |//
LL| |// Even though this function is used by `uses_crate.rs` (and
LL| |// counted), with substitutions for `T`, those instantiations are only generated
LL| |// when the generic function is actually used (from the binary, not from this
LL| |// library crate). So the test result shows coverage for all instantiated
LL| |// versions and their generic type substitutions, plus the `Unexecuted
LL| |// instantiation` message for the non-substituted version. This is valid, but
LL| |// unfortunately a little confusing.
LL| |//
LL| |// The library crate has its own coverage map, and the only way to show unused
LL| |// coverage of a generic function is to include the generic function in the
LL| |// coverage map, marked as an "unused function". If the library were used by
LL| |// another binary that never used this generic function, then it would be valid
LL| |// to show the unused generic, with unknown substitution (`_`).
LL| |//
LL| |// The alternative is to exclude all generics from being included in the "unused
LL| |// functions" list, which would then omit coverage results for
LL| |// `unused_generic_function<T>()`, below.
$DIR/uses_crate.rs:
LL| |// This test was failing on Linux for a while due to #110393 somehow making
LL| |// the unused functions not instrumented, but it seems to be fine now.
LL| |
LL| |// Validates coverage now works with optimizations
LL| |// compile-flags: -C opt-level=3
LL| |
LL| |#![allow(unused_assignments, unused_variables)]
LL| |
LL| |// aux-build:used_crate.rs
LL| |extern crate used_crate;
LL| |
LL| 1|fn main() {
LL| 1| used_crate::used_function();
LL| 1| let some_vec = vec![1, 2, 3, 4];
LL| 1| used_crate::used_only_from_bin_crate_generic_function(&some_vec);
LL| 1| used_crate::used_only_from_bin_crate_generic_function("used from bin uses_crate.rs");
LL| 1| used_crate::used_from_bin_crate_and_lib_crate_generic_function(some_vec);
LL| 1| used_crate::used_with_same_type_from_bin_crate_and_lib_crate_generic_function("interesting?");
LL| 1|}
|
