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Description
Hello,
I'm working on generating some valid C headers as property tests for bindgen, issue #970.
While filling in the generation logic I'm starting to come across code that makes
the csmith-fuzzing/predicate.py script cough. I don't know how many of these there
might be (or how many might be false alarms like #1151) so I'm open to just keeping a
public running list somewhere if raising issues as I encounter them isn't the preference.
I'm also open to sharing some of the generated
bonkers preliminary code
that bindgen is handling happily.
This also seems related to issue #684 which the property tests have run into as well.
This one only fails the csmith-fuzzing/predicate.py script though,
rustc seems to compile without errors so I thought I'd bring it up.
Sorry if the code looks insane, it's generated! 😰
Here's the result of rustup show:
Default host: x86_64-unknown-linux-gnu
installed toolchains
--------------------
stable-x86_64-unknown-linux-gnu
nightly-x86_64-unknown-linux-gnu (default)
active toolchain
----------------
nightly-x86_64-unknown-linux-gnu (default)
rustc 1.23.0-nightly (ff0f5de3b 2017-11-14)
Input C/C++ Header
struct {
char *decl_4_0[0][4]; // fails
} struct_2_0;
// struct {
// char decl_4_0[0][4]; // succeeds
// } struct_2_0;
// struct {
// char *decl_4_0[1][4]; // succeeds
// } struct_2_0;Bindgen Invocation
I've been using the csmith-fuzzing/predicate.py script to test so the failing invocation would look like this assuming that definition is in a header named prop_test.h
$ ./csmith-fuzzing/predicate.py prop_test.h
Actual Results
Script output:
Running: ['cargo', 'run', '--manifest-path', '/home/username/src/rust-bindgen/Cargo.toml', '--', 'prop_test.h', '-o', '/tmp/bindings-7_gwph30.rs', '--with-derive-partialeq', '--with-derive-eq', '--with-derive-partialord', '--with-derive-ord', '--with-derive-hash', '--with-derive-default']
Running: ['rustc', '--crate-type', 'lib', '--test', '-o', '/tmp/layout-tests-br4ipbog', '/tmp/bindings-7_gwph30.rs']
Running: ['/tmp/layout-tests-br4ipbog']
Error: running the compiled bindings' layout tests failed
+
+running 1 test
+test bindgen_test_layout__bindgen_ty_1 ... FAILED
+
+failures:
+
+---- bindgen_test_layout__bindgen_ty_1 stdout ----
+ thread 'bindgen_test_layout__bindgen_ty_1' panicked at 'assertion failed: `(left == right)`
+ left: `1`,
+ right: `8`: Alignment of _bindgen_ty_1', /tmp/bindings-7_gwph30.rs:52:4
+stack backtrace:
+ 0: 0x55f6f4d49f63 - std::sys::imp::backtrace::tracing::imp::unwind_backtrace::h58b4c7cfb400b18c
+ at /checkout/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
+ 1: 0x55f6f4d463ec - std::sys_common::backtrace::_print::h091e19687805d26e
+ at /checkout/src/libstd/sys_common/backtrace.rs:68
+ 2: 0x55f6f4d4c3b1 - std::panicking::default_hook::{{closure}}::h839e2a2e96c19d98
+ at /checkout/src/libstd/sys_common/backtrace.rs:57
+ at /checkout/src/libstd/panicking.rs:381
+ 3: 0x55f6f4d4c0ac - std::panicking::default_hook::h892c050099854db5
+ at /checkout/src/libstd/panicking.rs:391
+ 4: 0x55f6f4d4c884 - std::panicking::rust_panic_with_hook::h09c5f7a0435ac463
+ at /checkout/src/libstd/panicking.rs:577
+ 5: 0x55f6f4d4c6bc - std::panicking::begin_panic::h321753ef82401d62
+ at /checkout/src/libstd/panicking.rs:538
+ 6: 0x55f6f4d4c639 - std::panicking::begin_panic_fmt::h24fe390b9054223d
+ at /checkout/src/libstd/panicking.rs:522
+ 7: 0x55f6f4d0839c - bindings_7_gwph30::bindgen_test_layout__bindgen_ty_1::hbdde4efabb33c38f
+ 8: 0x55f6f4d17f61 - <F as test::FnBox<T>>::call_box::hc30672f430bdb600
+ at /checkout/src/libtest/lib.rs:1491
+ at /checkout/src/libcore/ops/function.rs:223
+ at /checkout/src/libtest/lib.rs:142
+ 9: 0x55f6f4d54ebe - __rust_maybe_catch_panic
+ at /checkout/src/libpanic_unwind/lib.rs:99
+ 10: 0x55f6f4d093b0 - std::sys_common::backtrace::__rust_begin_short_backtrace::h904f706bf2295342
+ at /checkout/src/libstd/panicking.rs:459
+ at /checkout/src/libstd/panic.rs:365
+ at /checkout/src/libtest/lib.rs:1430
+ at /checkout/src/libstd/sys_common/backtrace.rs:133
+ 11: 0x55f6f4d0a052 - std::panicking::try::do_call::hba965e573c3ab44f
+ at /checkout/src/libstd/thread/mod.rs:406
+ at /checkout/src/libstd/panic.rs:300
+ at /checkout/src/libstd/panicking.rs:480
+ 12: 0x55f6f4d54ebe - __rust_maybe_catch_panic
+ at /checkout/src/libpanic_unwind/lib.rs:99
+ 13: 0x55f6f4d11942 - <F as alloc::boxed::FnBox<A>>::call_box::h3f8cad64dddfc3c1
+ at /checkout/src/libstd/panicking.rs:459
+ at /checkout/src/libstd/panic.rs:365
+ at /checkout/src/libstd/thread/mod.rs:405
+ at /checkout/src/liballoc/boxed.rs:762
+ 14: 0x55f6f4d4b78b - std::sys::imp::thread::Thread::new::thread_start::he0774ede68aa21ab
+ at /checkout/src/liballoc/boxed.rs:772
+ at /checkout/src/libstd/sys_common/thread.rs:23
+ at /checkout/src/libstd/sys/unix/thread.rs:90
+ 15: 0x7f5de07de6b9 - start_thread
+ 16: 0x7f5de02fe3dc - clone
+ 17: 0x0 - <unknown>
+
+
+failures:
+ bindgen_test_layout__bindgen_ty_1
+
+test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out
+
rustc output when given the generated code:
warning: found zero-sized type composed only of phantom-data in a foreign-function.
--> err.rs:60:32
|
60 | pub static mut struct_2_0: _bindgen_ty_1;
| ^^^^^^^^^^^^^
|
= note: #[warn(improper_ctypes)] on by default
Generated code:
/* automatically generated by rust-bindgen */
#[repr(C)]
#[derive(Default)]
pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
impl<T> __IncompleteArrayField<T> {
#[inline]
pub fn new() -> Self {
__IncompleteArrayField(::std::marker::PhantomData)
}
#[inline]
pub unsafe fn as_ptr(&self) -> *const T {
::std::mem::transmute(self)
}
#[inline]
pub unsafe fn as_mut_ptr(&mut self) -> *mut T {
::std::mem::transmute(self)
}
#[inline]
pub unsafe fn as_slice(&self, len: usize) -> &[T] {
::std::slice::from_raw_parts(self.as_ptr(), len)
}
#[inline]
pub unsafe fn as_mut_slice(&mut self, len: usize) -> &mut [T] {
::std::slice::from_raw_parts_mut(self.as_mut_ptr(), len)
}
}
impl<T> ::std::fmt::Debug for __IncompleteArrayField<T> {
fn fmt(&self, fmt: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
fmt.write_str("__IncompleteArrayField")
}
}
impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
#[inline]
fn clone(&self) -> Self {
Self::new()
}
}
impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
#[repr(C)]
#[derive(Debug)]
pub struct _bindgen_ty_1 {
pub decl_4_0: __IncompleteArrayField<[*mut ::std::os::raw::c_char; 4usize]>,
}
#[test]
fn bindgen_test_layout__bindgen_ty_1() {
assert_eq!(
::std::mem::size_of::<_bindgen_ty_1>(),
0usize,
concat!("Size of: ", stringify!(_bindgen_ty_1))
);
assert_eq!(
::std::mem::align_of::<_bindgen_ty_1>(),
8usize,
concat!("Alignment of ", stringify!(_bindgen_ty_1))
);
}
extern "C" {
#[link_name = "\u{1}_Z10struct_2_0"]
pub static mut struct_2_0: _bindgen_ty_1;
}Expected Results
🙃 I'm not quite fluent enough in bindgen output to answer this one.