Rollup merge of #131351 - jieyouxu:yeet-the-valgrind, r=Kobzol

Remove valgrind test suite and support from compiletest, bootstrap and opt-dist

The `run-pass-valgrind` test suite is not exercised in CI, and as far as I'm aware nobody runs it (asked in https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/Are.20the.20valgrind.20tests.20even.20used.20by.20anyone.3F). What's remaining of valgrind support in compiletest isn't even properly hooked up with bootstrap.

The existing valgrind logic in compiletest is also straight up questionable, i.e.

1b3b8e7b02/src/tools/compiletest/src/runtest/valgrind.rs (L7-L12)

It just runs valgrind tests as `rpass` if no valgrind path is provided to compiletest from bootstrap -- but bootstrap doesn't even pass a valgrind path to compiletest in the first place, so this always ran as `rpass` tests. So what is this even testing?

So if it's not testing anything, let's delete it.

Closes #44816 by deleting the test suite :3

<img src="https://github.com/user-attachments/assets/99525bf7-e85b-40ba-9281-e4e1e275c4e8" width=300 />
This commit is contained in:
Jubilee 2024-10-07 11:10:54 -07:00 committed by GitHub
commit f88bfa34e1
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
25 changed files with 29 additions and 619 deletions

View File

@ -1394,12 +1394,6 @@ default_test!(Ui { path: "tests/ui", mode: "ui", suite: "ui" });
default_test!(Crashes { path: "tests/crashes", mode: "crashes", suite: "crashes" });
default_test!(RunPassValgrind {
path: "tests/run-pass-valgrind",
mode: "run-pass-valgrind",
suite: "run-pass-valgrind"
});
default_test!(Codegen { path: "tests/codegen", mode: "codegen", suite: "codegen" });
default_test!(CodegenUnits {

View File

@ -327,7 +327,6 @@ const PATH_REMAP: &[(&str, &[&str])] = &[
"tests/mir-opt",
"tests/pretty",
"tests/run-make",
"tests/run-pass-valgrind",
"tests/rustdoc",
"tests/rustdoc-gui",
"tests/rustdoc-js",
@ -852,7 +851,6 @@ impl<'a> Builder<'a> {
test::Tidy,
test::Ui,
test::Crashes,
test::RunPassValgrind,
test::Coverage,
test::CoverageMap,
test::CoverageRun,

View File

@ -53,7 +53,6 @@ macro_rules! string_enum {
string_enum! {
#[derive(Clone, Copy, PartialEq, Debug)]
pub enum Mode {
RunPassValgrind => "run-pass-valgrind",
Pretty => "pretty",
DebugInfo => "debuginfo",
Codegen => "codegen",
@ -207,13 +206,6 @@ pub struct Config {
/// Path to LLVM's bin directory.
pub llvm_bin_dir: Option<PathBuf>,
/// The valgrind path.
pub valgrind_path: Option<String>,
/// Whether to fail if we can't run run-pass-valgrind tests under valgrind
/// (or, alternatively, to silently run them like regular run-pass tests).
pub force_valgrind: bool,
/// The path to the Clang executable to run Clang-based tests with. If
/// `None` then these tests will be ignored.
pub run_clang_based_tests_with: Option<String>,

View File

@ -53,8 +53,6 @@ pub fn parse_config(args: Vec<String>) -> Config {
.reqopt("", "python", "path to python to use for doc tests", "PATH")
.optopt("", "jsondocck-path", "path to jsondocck to use for doc tests", "PATH")
.optopt("", "jsondoclint-path", "path to jsondoclint to use for doc tests", "PATH")
.optopt("", "valgrind-path", "path to Valgrind executable for Valgrind tests", "PROGRAM")
.optflag("", "force-valgrind", "fail if Valgrind tests cannot be run under Valgrind")
.optopt("", "run-clang-based-tests-with", "path to Clang executable", "PATH")
.optopt("", "llvm-filecheck", "path to LLVM's FileCheck binary", "DIR")
.reqopt("", "src-base", "directory to scan for test files", "PATH")
@ -65,7 +63,7 @@ pub fn parse_config(args: Vec<String>) -> Config {
"",
"mode",
"which sort of compile tests to run",
"run-pass-valgrind | pretty | debug-info | codegen | rustdoc \
"pretty | debug-info | codegen | rustdoc \
| rustdoc-json | codegen-units | incremental | run-make | ui \
| js-doc-test | mir-opt | assembly | crashes",
)
@ -269,8 +267,6 @@ pub fn parse_config(args: Vec<String>) -> Config {
python: matches.opt_str("python").unwrap(),
jsondocck_path: matches.opt_str("jsondocck-path"),
jsondoclint_path: matches.opt_str("jsondoclint-path"),
valgrind_path: matches.opt_str("valgrind-path"),
force_valgrind: matches.opt_present("force-valgrind"),
run_clang_based_tests_with: matches.opt_str("run-clang-based-tests-with"),
llvm_filecheck: matches.opt_str("llvm-filecheck").map(PathBuf::from),
llvm_bin_dir: matches.opt_str("llvm-bin-dir").map(PathBuf::from),

View File

@ -18,10 +18,6 @@ fn main() {
let config = Arc::new(parse_config(env::args().collect()));
if config.valgrind_path.is_none() && config.force_valgrind {
panic!("Can't find Valgrind to run Valgrind tests");
}
if !config.has_tidy && config.mode == Mode::Rustdoc {
eprintln!("warning: `tidy` is not installed; diffs will not be generated");
}

View File

@ -20,9 +20,9 @@ use tracing::*;
use crate::common::{
Assembly, Codegen, CodegenUnits, CompareMode, Config, CoverageMap, CoverageRun, Crashes,
DebugInfo, Debugger, FailMode, Incremental, JsDocTest, MirOpt, PassMode, Pretty, RunMake,
RunPassValgrind, Rustdoc, RustdocJson, TestPaths, UI_EXTENSIONS, UI_FIXED, UI_RUN_STDERR,
UI_RUN_STDOUT, UI_STDERR, UI_STDOUT, UI_SVG, UI_WINDOWS_SVG, Ui, expected_output_path,
incremental_dir, output_base_dir, output_base_name, output_testname_unique,
Rustdoc, RustdocJson, TestPaths, UI_EXTENSIONS, UI_FIXED, UI_RUN_STDERR, UI_RUN_STDOUT,
UI_STDERR, UI_STDOUT, UI_SVG, UI_WINDOWS_SVG, Ui, expected_output_path, incremental_dir,
output_base_dir, output_base_name, output_testname_unique,
};
use crate::compute_diff::{write_diff, write_filtered_diff};
use crate::errors::{self, Error, ErrorKind};
@ -49,7 +49,6 @@ mod run_make;
mod rustdoc;
mod rustdoc_json;
mod ui;
mod valgrind;
// tidy-alphabet-end
#[cfg(test)]
@ -253,7 +252,6 @@ impl<'test> TestCx<'test> {
self.fatal("cannot use should-ice in a test that is not cfail");
}
match self.config.mode {
RunPassValgrind => self.run_valgrind_test(),
Pretty => self.run_pretty_test(),
DebugInfo => self.run_debuginfo_test(),
Codegen => self.run_codegen_test(),
@ -1500,8 +1498,7 @@ impl<'test> TestCx<'test> {
Crashes => {
set_mir_dump_dir(&mut rustc);
}
RunPassValgrind | Pretty | DebugInfo | Rustdoc | RustdocJson | RunMake
| CodegenUnits | JsDocTest => {
Pretty | DebugInfo | Rustdoc | RustdocJson | RunMake | CodegenUnits | JsDocTest => {
// do not use JSON output
}
}
@ -2655,33 +2652,6 @@ impl<'test> TestCx<'test> {
}
}
// FIXME(jieyouxu): `run_rpass_test` is hoisted out here and not in incremental because
// apparently valgrind test falls back to `run_rpass_test` if valgrind isn't available, which
// seems highly questionable to me.
fn run_rpass_test(&self) {
let emit_metadata = self.should_emit_metadata(self.pass_mode());
let should_run = self.run_if_enabled();
let proc_res = self.compile_test(should_run, emit_metadata);
if !proc_res.status.success() {
self.fatal_proc_rec("compilation failed!", &proc_res);
}
// FIXME(#41968): Move this check to tidy?
if !errors::load_errors(&self.testpaths.file, self.revision).is_empty() {
self.fatal("run-pass tests with expected warnings should be moved to ui/");
}
if let WillExecute::Disabled = should_run {
return;
}
let proc_res = self.exec_compiled_test();
if !proc_res.status.success() {
self.fatal_proc_rec("test run failed!", &proc_res);
}
}
fn aggressive_rm_rf(&self, path: &Path) -> io::Result<()> {
for e in path.read_dir()? {
let entry = e?;

View File

@ -1,10 +1,6 @@
use super::{TestCx, WillExecute};
use crate::errors;
// FIXME(jieyouxu): `run_rpass_test` got hoisted out of this because apparently valgrind falls back
// to `run_rpass_test` if valgrind isn't available, which is questionable, but keeping it for
// refactoring changes to preserve current behavior.
impl TestCx<'_> {
pub(super) fn run_incremental_test(&self) {
// Basic plan for a test incremental/foo/bar.rs:
@ -73,6 +69,30 @@ impl TestCx<'_> {
}
}
fn run_rpass_test(&self) {
let emit_metadata = self.should_emit_metadata(self.pass_mode());
let should_run = self.run_if_enabled();
let proc_res = self.compile_test(should_run, emit_metadata);
if !proc_res.status.success() {
self.fatal_proc_rec("compilation failed!", &proc_res);
}
// FIXME(#41968): Move this check to tidy?
if !errors::load_errors(&self.testpaths.file, self.revision).is_empty() {
self.fatal("run-pass tests with expected warnings should be moved to ui/");
}
if let WillExecute::Disabled = should_run {
return;
}
let proc_res = self.exec_compiled_test();
if !proc_res.status.success() {
self.fatal_proc_rec("test run failed!", &proc_res);
}
}
fn run_cfail_test(&self) {
let pm = self.pass_mode();
let proc_res = self.compile_test(WillExecute::No, self.should_emit_metadata(pm));
@ -115,12 +135,6 @@ impl TestCx<'_> {
let proc_res = self.exec_compiled_test();
// The value our Makefile configures valgrind to return on failure
const VALGRIND_ERR: i32 = 100;
if proc_res.status.code() == Some(VALGRIND_ERR) {
self.fatal_proc_rec("run-fail test isn't valgrind-clean!", &proc_res);
}
let output_to_check = self.get_output(&proc_res);
self.check_correct_failure_status(&proc_res);
self.check_all_error_patterns(&output_to_check, &proc_res, pm);

View File

@ -1,34 +0,0 @@
use super::{Emit, TestCx, WillExecute};
impl TestCx<'_> {
pub(super) fn run_valgrind_test(&self) {
assert!(self.revision.is_none(), "revisions not relevant here");
// FIXME(jieyouxu): does this really make any sense? If a valgrind test isn't testing
// valgrind, what is it even testing?
if self.config.valgrind_path.is_none() {
assert!(!self.config.force_valgrind);
return self.run_rpass_test();
}
let should_run = self.run_if_enabled();
let mut proc_res = self.compile_test(should_run, Emit::None);
if !proc_res.status.success() {
self.fatal_proc_rec("compilation failed!", &proc_res);
}
if let WillExecute::Disabled = should_run {
return;
}
let mut new_config = self.config.clone();
new_config.runner = new_config.valgrind_path.clone();
let new_cx = TestCx { config: &new_config, ..*self };
proc_res = new_cx.exec_compiled_test();
if !proc_res.status.success() {
self.fatal_proc_rec("test run failed!", &proc_res);
}
}
}

View File

@ -96,7 +96,6 @@ llvm-config = "{llvm_config}"
"tests/incremental",
"tests/mir-opt",
"tests/pretty",
"tests/run-pass-valgrind",
"tests/ui",
"tests/crashes",
];

View File

@ -1,34 +0,0 @@
#![allow(dead_code, cenum_impl_drop_cast)]
// check dtor calling order when casting enums.
use std::mem;
use std::sync::atomic;
use std::sync::atomic::Ordering;
enum E {
A = 0,
B = 1,
C = 2,
}
static FLAG: atomic::AtomicUsize = atomic::AtomicUsize::new(0);
impl Drop for E {
fn drop(&mut self) {
// avoid dtor loop
unsafe { mem::forget(mem::replace(self, E::B)) };
FLAG.store(FLAG.load(Ordering::SeqCst) + 1, Ordering::SeqCst);
}
}
fn main() {
assert_eq!(FLAG.load(Ordering::SeqCst), 0);
{
let e = E::C;
assert_eq!(e as u32, 2);
assert_eq!(FLAG.load(Ordering::SeqCst), 1);
}
assert_eq!(FLAG.load(Ordering::SeqCst), 1);
}

View File

@ -1,28 +0,0 @@
// This would previously leak the Box<Trait> because we wouldn't
// schedule cleanups when auto borrowing trait objects.
// This program should be valgrind clean.
static mut DROP_RAN: bool = false;
struct Foo;
impl Drop for Foo {
fn drop(&mut self) {
unsafe {
DROP_RAN = true;
}
}
}
trait Trait {
fn dummy(&self) {}
}
impl Trait for Foo {}
pub fn main() {
{
let _x: &Trait = &*(Box::new(Foo) as Box<Trait>);
}
unsafe {
assert!(DROP_RAN);
}
}

View File

@ -1,5 +0,0 @@
fn main() {
let _ = std::io::stdin();
let _ = std::io::stdout();
let _ = std::io::stderr();
}

View File

@ -1,21 +0,0 @@
// Check that coercions are propagated through match and if expressions.
//@ pretty-expanded FIXME #23616
use std::boxed::Box;
pub fn main() {
let _: Box<[isize]> = if true { Box::new([1, 2, 3]) } else { Box::new([1]) };
let _: Box<[isize]> = match true {
true => Box::new([1, 2, 3]),
false => Box::new([1]),
};
// Check we don't get over-keen at propagating coercions in the case of casts.
let x = if true { 42 } else { 42u8 } as u16;
let x = match true {
true => 42,
false => 42u8,
} as u16;
}

View File

@ -1,31 +0,0 @@
// Check that coercions are propagated through match and if expressions.
//@ pretty-expanded FIXME #23616
pub fn main() {
let _: Box<[isize]> = if true {
let b: Box<_> = Box::new([1, 2, 3]);
b
} else {
let b: Box<_> = Box::new([1]);
b
};
let _: Box<[isize]> = match true {
true => {
let b: Box<_> = Box::new([1, 2, 3]);
b
}
false => {
let b: Box<_> = Box::new([1]);
b
}
};
// Check we don't get over-keen at propagating coercions in the case of casts.
let x = if true { 42 } else { 42u8 } as u16;
let x = match true {
true => 42,
false => 42u8,
} as u16;
}

View File

@ -1,43 +0,0 @@
//@ ignore-emscripten
thread_local!(static FOO: Foo = Foo);
thread_local!(static BAR: Bar = Bar(1));
thread_local!(static BAZ: Baz = Baz);
static mut HIT: bool = false;
struct Foo;
struct Bar(i32);
struct Baz;
impl Drop for Foo {
fn drop(&mut self) {
BAR.with(|_| {});
}
}
impl Drop for Bar {
fn drop(&mut self) {
assert_eq!(self.0, 1);
self.0 = 2;
BAZ.with(|_| {});
assert_eq!(self.0, 2);
}
}
impl Drop for Baz {
fn drop(&mut self) {
unsafe {
HIT = true;
}
}
}
fn main() {
std::thread::spawn(|| {
FOO.with(|_| {});
})
.join()
.unwrap();
assert!(unsafe { HIT });
}

View File

@ -1,28 +0,0 @@
static mut DROP_RAN: bool = false;
struct Foo;
impl Drop for Foo {
fn drop(&mut self) {
unsafe {
DROP_RAN = true;
}
}
}
trait Trait {
fn dummy(&self) {}
}
impl Trait for Foo {}
struct Fat<T: ?Sized> {
f: T,
}
pub fn main() {
{
let _x: Box<Fat<Trait>> = Box::<Fat<Foo>>::new(Fat { f: Foo });
}
unsafe {
assert!(DROP_RAN);
}
}

View File

@ -1,23 +0,0 @@
static mut DROP_RAN: isize = 0;
struct Foo;
impl Drop for Foo {
fn drop(&mut self) {
unsafe {
DROP_RAN += 1;
}
}
}
struct Fat<T: ?Sized> {
f: T,
}
pub fn main() {
{
let _x: Box<Fat<[Foo]>> = Box::<Fat<[Foo; 3]>>::new(Fat { f: [Foo, Foo, Foo] });
}
unsafe {
assert_eq!(DROP_RAN, 3);
}
}

View File

@ -1,26 +0,0 @@
#![feature(unsized_tuple_coercion)]
static mut DROP_RAN: bool = false;
struct Foo;
impl Drop for Foo {
fn drop(&mut self) {
unsafe {
DROP_RAN = true;
}
}
}
trait Trait {
fn dummy(&self) {}
}
impl Trait for Foo {}
pub fn main() {
{
let _x: Box<(i32, Trait)> = Box::<(i32, Foo)>::new((42, Foo));
}
unsafe {
assert!(DROP_RAN);
}
}

View File

@ -1,21 +0,0 @@
#![feature(unsized_tuple_coercion)]
static mut DROP_RAN: isize = 0;
struct Foo;
impl Drop for Foo {
fn drop(&mut self) {
unsafe {
DROP_RAN += 1;
}
}
}
pub fn main() {
{
let _x: Box<(i32, [Foo])> = Box::<(i32, [Foo; 3])>::new((42, [Foo, Foo, Foo]));
}
unsafe {
assert_eq!(DROP_RAN, 3);
}
}

View File

@ -1,19 +0,0 @@
//@ ignore-wasm32 no subprocess support
//@ ignore-sgx no processes
//@ ignore-apple this needs valgrind 3.11 or higher; see
// https://github.com/rust-lang/rust/pull/30365#issuecomment-165763679
use std::env;
use std::process::{Command, exit};
fn main() {
if env::args().len() > 1 {
print!("hello!");
exit(0);
} else {
let out = Command::new(env::args().next().unwrap()).arg("foo").output().unwrap();
assert!(out.status.success());
assert_eq!(String::from_utf8(out.stdout).unwrap(), "hello!");
assert_eq!(String::from_utf8(out.stderr).unwrap(), "");
}
}

View File

@ -1,12 +0,0 @@
use std::alloc::System;
use std::collections::VecDeque;
#[global_allocator]
static ALLOCATOR: System = System;
fn main() {
let mut deque = VecDeque::with_capacity(32);
deque.push_front(0);
deque.reserve(31);
deque.push_back(0);
}

View File

@ -1,55 +0,0 @@
#![feature(unsized_locals)]
#![feature(unboxed_closures)]
#![feature(tuple_trait)]
pub trait FnOnce<Args: std::marker::Tuple> {
type Output;
extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
}
struct A;
impl FnOnce<()> for A {
type Output = String;
extern "rust-call" fn call_once(self, (): ()) -> Self::Output {
format!("hello")
}
}
struct B(i32);
impl FnOnce<()> for B {
type Output = String;
extern "rust-call" fn call_once(self, (): ()) -> Self::Output {
format!("{}", self.0)
}
}
struct C(String);
impl FnOnce<()> for C {
type Output = String;
extern "rust-call" fn call_once(self, (): ()) -> Self::Output {
self.0
}
}
struct D(Box<String>);
impl FnOnce<()> for D {
type Output = String;
extern "rust-call" fn call_once(self, (): ()) -> Self::Output {
*self.0
}
}
fn main() {
let x = *(Box::new(A) as Box<dyn FnOnce<(), Output = String>>);
assert_eq!(x.call_once(()), format!("hello"));
let x = *(Box::new(B(42)) as Box<dyn FnOnce<(), Output = String>>);
assert_eq!(x.call_once(()), format!("42"));
let x = *(Box::new(C(format!("jumping fox"))) as Box<dyn FnOnce<(), Output = String>>);
assert_eq!(x.call_once(()), format!("jumping fox"));
let x = *(Box::new(D(Box::new(format!("lazy dog")))) as Box<dyn FnOnce<(), Output = String>>);
assert_eq!(x.call_once(()), format!("lazy dog"));
}

View File

@ -1,69 +0,0 @@
#![feature(unsized_locals)]
#![feature(unboxed_closures)]
#![feature(tuple_trait)]
pub trait FnOnce<Args: std::marker::Tuple> {
type Output;
extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
}
struct A;
impl FnOnce<(String, Box<str>)> for A {
type Output = String;
extern "rust-call" fn call_once(self, (s1, s2): (String, Box<str>)) -> Self::Output {
assert_eq!(&s1 as &str, "s1");
assert_eq!(&s2 as &str, "s2");
format!("hello")
}
}
struct B(i32);
impl FnOnce<(String, Box<str>)> for B {
type Output = String;
extern "rust-call" fn call_once(self, (s1, s2): (String, Box<str>)) -> Self::Output {
assert_eq!(&s1 as &str, "s1");
assert_eq!(&s2 as &str, "s2");
format!("{}", self.0)
}
}
struct C(String);
impl FnOnce<(String, Box<str>)> for C {
type Output = String;
extern "rust-call" fn call_once(self, (s1, s2): (String, Box<str>)) -> Self::Output {
assert_eq!(&s1 as &str, "s1");
assert_eq!(&s2 as &str, "s2");
self.0
}
}
struct D(Box<String>);
impl FnOnce<(String, Box<str>)> for D {
type Output = String;
extern "rust-call" fn call_once(self, (s1, s2): (String, Box<str>)) -> Self::Output {
assert_eq!(&s1 as &str, "s1");
assert_eq!(&s2 as &str, "s2");
*self.0
}
}
fn main() {
let (s1, s2) = (format!("s1"), format!("s2").into_boxed_str());
let x = *(Box::new(A) as Box<dyn FnOnce<(String, Box<str>), Output = String>>);
assert_eq!(x.call_once((s1, s2)), format!("hello"));
let (s1, s2) = (format!("s1"), format!("s2").into_boxed_str());
let x = *(Box::new(B(42)) as Box<dyn FnOnce<(String, Box<str>), Output = String>>);
assert_eq!(x.call_once((s1, s2)), format!("42"));
let (s1, s2) = (format!("s1"), format!("s2").into_boxed_str());
let x = *(Box::new(C(format!("jumping fox")))
as Box<dyn FnOnce<(String, Box<str>), Output = String>>);
assert_eq!(x.call_once((s1, s2)), format!("jumping fox"));
let (s1, s2) = (format!("s1"), format!("s2").into_boxed_str());
let x = *(Box::new(D(Box::new(format!("lazy dog"))))
as Box<dyn FnOnce<(String, Box<str>), Output = String>>);
assert_eq!(x.call_once((s1, s2)), format!("lazy dog"));
}

View File

@ -1,48 +0,0 @@
#![feature(unsized_locals)]
pub trait Foo {
fn foo(self) -> String;
}
struct A;
impl Foo for A {
fn foo(self) -> String {
format!("hello")
}
}
struct B(i32);
impl Foo for B {
fn foo(self) -> String {
format!("{}", self.0)
}
}
struct C(String);
impl Foo for C {
fn foo(self) -> String {
self.0
}
}
struct D(Box<String>);
impl Foo for D {
fn foo(self) -> String {
*self.0
}
}
fn main() {
let x = *(Box::new(A) as Box<dyn Foo>);
assert_eq!(x.foo(), format!("hello"));
let x = *(Box::new(B(42)) as Box<dyn Foo>);
assert_eq!(x.foo(), format!("42"));
let x = *(Box::new(C(format!("jumping fox"))) as Box<dyn Foo>);
assert_eq!(x.foo(), format!("jumping fox"));
let x = *(Box::new(D(Box::new(format!("lazy dog")))) as Box<dyn Foo>);
assert_eq!(x.foo(), format!("lazy dog"));
}

View File

@ -1,52 +0,0 @@
#![allow(incomplete_features)]
#![feature(unsized_locals, unsized_fn_params)]
use std::fmt;
fn gen_foo() -> Box<fmt::Display> {
Box::new(Box::new("foo"))
}
fn foo(x: fmt::Display) {
assert_eq!(x.to_string(), "foo");
}
fn foo_indirect(x: fmt::Display) {
foo(x);
}
fn main() {
foo(*gen_foo());
foo_indirect(*gen_foo());
{
let x: fmt::Display = *gen_foo();
foo(x);
}
{
let x: fmt::Display = *gen_foo();
let y: fmt::Display = *gen_foo();
foo(x);
foo(y);
}
{
let mut cnt: usize = 3;
let x = loop {
let x: fmt::Display = *gen_foo();
if cnt == 0 {
break x;
} else {
cnt -= 1;
}
};
foo(x);
}
{
let x: fmt::Display = *gen_foo();
let x = if true { x } else { *gen_foo() };
foo(x);
}
}