From 7f6034862d0a22c7337eb428c67fcdb23b9168ae Mon Sep 17 00:00:00 2001 From: Ralf Jung Date: Sat, 23 Jul 2022 08:44:16 -0400 Subject: [PATCH] pass clippy::cast_possible_truncation --- src/lib.rs | 1 + src/shims/backtrace.rs | 6 ++++-- src/shims/foreign_items.rs | 12 ++++++++---- src/shims/intrinsics/mod.rs | 5 +---- src/shims/unix/fs.rs | 4 ++-- src/shims/windows/dlsym.rs | 3 ++- src/shims/windows/foreign_items.rs | 2 +- 7 files changed, 19 insertions(+), 14 deletions(-) diff --git a/src/lib.rs b/src/lib.rs index c1b0c4afca6..caae17b2022 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -29,6 +29,7 @@ clippy::cast_possible_wrap, // unsigned -> signed clippy::cast_sign_loss, // signed -> unsigned clippy::cast_lossless, + clippy::cast_possible_truncation, )] extern crate rustc_apfloat; diff --git a/src/shims/backtrace.rs b/src/shims/backtrace.rs index 54ab8665ce3..9182b2a7217 100644 --- a/src/shims/backtrace.rs +++ b/src/shims/backtrace.rs @@ -171,9 +171,11 @@ fn handle_miri_resolve_frame( ); } - let lineno: u32 = lo.line as u32; + // `u32` is not enough to fit line/colno, which can be `usize`. It seems unlikely that a + // file would have more than 2^32 lines or columns, but whatever, just default to 0. + let lineno: u32 = u32::try_from(lo.line).unwrap_or(0); // `lo.col` is 0-based - add 1 to make it 1-based for the caller. - let colno: u32 = lo.col.0 as u32 + 1; + let colno: u32 = u32::try_from(lo.col.0 + 1).unwrap_or(0); let dest = this.force_allocation(dest)?; if let ty::Adt(adt, _) = dest.layout.ty.kind() { diff --git a/src/shims/foreign_items.rs b/src/shims/foreign_items.rs index 317eab082c0..208e7ea788f 100644 --- a/src/shims/foreign_items.rs +++ b/src/shims/foreign_items.rs @@ -82,8 +82,12 @@ fn malloc( let align = this.min_align(size, kind); let ptr = this.allocate_ptr(Size::from_bytes(size), align, kind.into())?; if zero_init { - // We just allocated this, the access is definitely in-bounds. - this.write_bytes_ptr(ptr.into(), iter::repeat(0u8).take(size as usize)).unwrap(); + // We just allocated this, the access is definitely in-bounds and fits into our address space. + this.write_bytes_ptr( + ptr.into(), + iter::repeat(0u8).take(usize::try_from(size).unwrap()), + ) + .unwrap(); } Ok(ptr.into()) } @@ -529,7 +533,7 @@ fn emulate_foreign_item_by_name( let val = this.read_scalar(val)?.to_i32()?; let num = this.read_scalar(num)?.to_machine_usize(this)?; // The docs say val is "interpreted as unsigned char". - #[allow(clippy::cast_sign_loss)] + #[allow(clippy::cast_sign_loss, clippy::cast_possible_truncation)] let val = val as u8; if let Some(idx) = this @@ -550,7 +554,7 @@ fn emulate_foreign_item_by_name( let val = this.read_scalar(val)?.to_i32()?; let num = this.read_scalar(num)?.to_machine_usize(this)?; // The docs say val is "interpreted as unsigned char". - #[allow(clippy::cast_sign_loss)] + #[allow(clippy::cast_sign_loss, clippy::cast_possible_truncation)] let val = val as u8; let idx = this diff --git a/src/shims/intrinsics/mod.rs b/src/shims/intrinsics/mod.rs index c07ed8b2948..4c2d08ffcea 100644 --- a/src/shims/intrinsics/mod.rs +++ b/src/shims/intrinsics/mod.rs @@ -117,10 +117,7 @@ fn emulate_intrinsic_by_name( let byte_count = ty_layout.size.checked_mul(count, this).ok_or_else(|| { err_ub_format!("overflow computing total size of `{intrinsic_name}`") })?; - this.write_bytes_ptr( - ptr, - iter::repeat(val_byte).take(byte_count.bytes() as usize), - )?; + this.write_bytes_ptr(ptr, iter::repeat(val_byte).take(byte_count.bytes_usize()))?; } // Floating-point operations diff --git a/src/shims/unix/fs.rs b/src/shims/unix/fs.rs index 3b82cb3c4eb..dc31237a319 100644 --- a/src/shims/unix/fs.rs +++ b/src/shims/unix/fs.rs @@ -785,8 +785,8 @@ fn read( trace!("read: FD mapped to {:?}", file_descriptor); // We want to read at most `count` bytes. We are sure that `count` is not negative // because it was a target's `usize`. Also we are sure that its smaller than - // `usize::MAX` because it is a host's `isize`. - let mut bytes = vec![0; count as usize]; + // `usize::MAX` because it is bounded by the host's `isize`. + let mut bytes = vec![0; usize::try_from(count).unwrap()]; // `File::read` never returns a value larger than `count`, // so this cannot fail. let result = diff --git a/src/shims/windows/dlsym.rs b/src/shims/windows/dlsym.rs index 51b0e3b83d4..eab5f99c878 100644 --- a/src/shims/windows/dlsym.rs +++ b/src/shims/windows/dlsym.rs @@ -84,7 +84,8 @@ fn call_dlsym( } else { io::stderr().write(buf_cont) }; - res.ok().map(|n| n as u32) + // We write at most `n` bytes, which is a `u32`, so we cannot have written more than that. + res.ok().map(|n| u32::try_from(n).unwrap()) } else { throw_unsup_format!( "on Windows, writing to anything except stdout/stderr is not supported" diff --git a/src/shims/windows/foreign_items.rs b/src/shims/windows/foreign_items.rs index 3f4b8b14002..29afe52cafd 100644 --- a/src/shims/windows/foreign_items.rs +++ b/src/shims/windows/foreign_items.rs @@ -116,7 +116,7 @@ fn emulate_foreign_item_by_name( // Initialize with `0`. this.write_bytes_ptr( system_info.ptr, - iter::repeat(0u8).take(system_info.layout.size.bytes() as usize), + iter::repeat(0u8).take(system_info.layout.size.bytes_usize()), )?; // Set selected fields. let word_layout = this.machine.layouts.u16;