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|
1| |#![allow(unused_assignments, unused_variables)]
2| |// compile-flags: -C opt-level=3 # validates coverage now works with optimizations
3| |use std::fmt::Debug;
4| |
5| 1|pub fn used_function() {
6| 1| // Initialize test constants in a way that cannot be determined at compile time, to ensure
7| 1| // rustc and LLVM cannot optimize out statements (or coverage counters) downstream from
8| 1| // dependent conditions.
9| 1| let is_true = std::env::args().len() == 1;
10| 1| let mut countdown = 0;
11| 1| if is_true {
12| 1| countdown = 10;
13| 1| }
^0
14| 1| use_this_lib_crate();
15| 1|}
16| |
17| 2|pub fn used_only_from_bin_crate_generic_function<T: Debug>(arg: T) {
18| 2| println!("used_only_from_bin_crate_generic_function with {:?}", arg);
19| 2|}
------------------
| used_crate::used_only_from_bin_crate_generic_function::<&str>:
| 17| 1|pub fn used_only_from_bin_crate_generic_function<T: Debug>(arg: T) {
| 18| 1| println!("used_only_from_bin_crate_generic_function with {:?}", arg);
| 19| 1|}
------------------
| used_crate::used_only_from_bin_crate_generic_function::<&alloc::vec::Vec<i32>>:
| 17| 1|pub fn used_only_from_bin_crate_generic_function<T: Debug>(arg: T) {
| 18| 1| println!("used_only_from_bin_crate_generic_function with {:?}", arg);
| 19| 1|}
------------------
| Unexecuted instantiation: used_crate::used_only_from_bin_crate_generic_function::<_>
------------------
20| |// Expect for above function: `Unexecuted instantiation` (see below)
21| 2|pub fn used_only_from_this_lib_crate_generic_function<T: Debug>(arg: T) {
22| 2| println!("used_only_from_this_lib_crate_generic_function with {:?}", arg);
23| 2|}
------------------
| used_crate::used_only_from_this_lib_crate_generic_function::<alloc::vec::Vec<i32>>:
| 21| 1|pub fn used_only_from_this_lib_crate_generic_function<T: Debug>(arg: T) {
| 22| 1| println!("used_only_from_this_lib_crate_generic_function with {:?}", arg);
| 23| 1|}
------------------
| used_crate::used_only_from_this_lib_crate_generic_function::<&str>:
| 21| 1|pub fn used_only_from_this_lib_crate_generic_function<T: Debug>(arg: T) {
| 22| 1| println!("used_only_from_this_lib_crate_generic_function with {:?}", arg);
| 23| 1|}
------------------
24| |
25| 2|pub fn used_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
26| 2| println!("used_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
27| 2|}
------------------
| used_crate::used_from_bin_crate_and_lib_crate_generic_function::<alloc::vec::Vec<i32>>:
| 25| 1|pub fn used_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
| 26| 1| println!("used_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
| 27| 1|}
------------------
| used_crate::used_from_bin_crate_and_lib_crate_generic_function::<&str>:
| 25| 1|pub fn used_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
| 26| 1| println!("used_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
| 27| 1|}
------------------
28| |
29| 2|pub fn used_with_same_type_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
30| 2| println!("used_with_same_type_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
31| 2|}
------------------
| used_crate::used_with_same_type_from_bin_crate_and_lib_crate_generic_function::<&str>:
| 29| 1|pub fn used_with_same_type_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
| 30| 1| println!("used_with_same_type_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
| 31| 1|}
------------------
| used_crate::used_with_same_type_from_bin_crate_and_lib_crate_generic_function::<&str>:
| 29| 1|pub fn used_with_same_type_from_bin_crate_and_lib_crate_generic_function<T: Debug>(arg: T) {
| 30| 1| println!("used_with_same_type_from_bin_crate_and_lib_crate_generic_function with {:?}", arg);
| 31| 1|}
------------------
32| |
33| 0|pub fn unused_generic_function<T: Debug>(arg: T) {
34| 0| println!("unused_generic_function with {:?}", arg);
35| 0|}
36| |
37| 0|pub fn unused_function() {
38| 0| let is_true = std::env::args().len() == 1;
39| 0| let mut countdown = 2;
40| 0| if !is_true {
41| 0| countdown = 20;
42| 0| }
43| 0|}
44| |
45| 0|fn unused_private_function() {
46| 0| let is_true = std::env::args().len() == 1;
47| 0| let mut countdown = 2;
48| 0| if !is_true {
49| 0| countdown = 20;
50| 0| }
51| 0|}
52| |
53| 1|fn use_this_lib_crate() {
54| 1| used_from_bin_crate_and_lib_crate_generic_function("used from library used_crate.rs");
55| 1| used_with_same_type_from_bin_crate_and_lib_crate_generic_function(
56| 1| "used from library used_crate.rs",
57| 1| );
58| 1| let some_vec = vec![5, 6, 7, 8];
59| 1| used_only_from_this_lib_crate_generic_function(some_vec);
60| 1| used_only_from_this_lib_crate_generic_function("used ONLY from library used_crate.rs");
61| 1|}
62| |
63| |// FIXME(#79651): "Unexecuted instantiation" errors appear in coverage results,
64| |// for example:
65| |//
66| |// | Unexecuted instantiation: used_crate::used_only_from_bin_crate_generic_function::<_>
67| |//
68| |// These notices appear when `llvm-cov` shows instantiations. This may be a
69| |// default option, but it can be suppressed with:
70| |//
71| |// ```shell
72| |// $ `llvm-cov show --show-instantiations=0 ...`
73| |// ```
74| |//
75| |// The notice is triggered because the function is unused by the library itself,
76| |// and when the library is compiled, a synthetic function is generated, so
77| |// unused function coverage can be reported. Coverage can be skipped for unused
78| |// generic functions with:
79| |//
80| |// ```shell
81| |// $ `rustc -Zunstable-options -C instrument-coverage=except-unused-generics ...`
82| |// ```
83| |//
84| |// Even though this function is used by `uses_crate.rs` (and
85| |// counted), with substitutions for `T`, those instantiations are only generated
86| |// when the generic function is actually used (from the binary, not from this
87| |// library crate). So the test result shows coverage for all instantiated
88| |// versions and their generic type substitutions, plus the `Unexecuted
89| |// instantiation` message for the non-substituted version. This is valid, but
90| |// unfortunately a little confusing.
91| |//
92| |// The library crate has its own coverage map, and the only way to show unused
93| |// coverage of a generic function is to include the generic function in the
94| |// coverage map, marked as an "unused function". If the library were used by
95| |// another binary that never used this generic function, then it would be valid
96| |// to show the unused generic, with unknown substitution (`_`).
97| |//
98| |// The alternative is to exclude all generics from being included in the "unused
99| |// functions" list, which would then omit coverage results for
100| |// `unused_generic_function<T>()`, below.
|
