Emit coercion suggestions in more places
Fixes#66910
We have several different kinds of suggestions we can try to make when
type coercion fails. However, we were previously only emitting these
suggestions from `demand_coerce_diag`. This resulted in the compiler
failing to emit applicable suggestions in several different cases, such
as when the implicit return value of a function had the wrong type.
This commit adds a new `emit_coerce_suggestions` method, which tries to
emit a number of related suggestions. This method is called from both
`demand_coerce_diag` and `CoerceMany::coerce_inner`, which covers a much
wider range of cases than before.
We now suggest using `.await` in more cases where it is applicable,
among other improvements.
I'm not happy about disabling the `issue-59756`, but from what I can tell, the suggestion infrastructure in rustc lacks any way of indicating mutually exclusive suggestions (and compiletest lacks a way to only apply a subset of available suggestions).
Add `{f32,f64}::approx_unchecked_to<Int>` unsafe methods
As discussed in https://github.com/rust-lang/rust/issues/10184
Currently, casting a floating point number to an integer with `as` is Undefined Behavior if the value is out of range. `-Z saturating-float-casts` fixes this soundness hole by making `as` “saturate” to the maximum or minimum value of the integer type (or zero for `NaN`), but has measurable negative performance impact in some benchmarks. There is some consensus in that thread for enabling saturation by default anyway, but provide an `unsafe fn` alternative for users who know through some other mean that their values are in range.
<del>The “fit” wording is copied from https://llvm.org/docs/LangRef.html#fptoui-to-instruction, but I’m not certain what it means exactly. Presumably this is after rounding towards zero, and the doc-test with `i8::MIN` seems to confirm this.</del> Clang presumably uses those LLVM intrinsics to implement C and C++ casts, whose respective standard specify that the value *after truncating to keep its integral part* must be representable in the target type.
I spent a while debugging a strage linker error about an outdated `glibc` version, only to discover that it was caused by a stale `obj` directory. It wasn't obviously to be that using the same obj dir with multiple Docker images (for the same target triple) could be a problem.
This commit adds a note to the README, which should hopefully be helpful to anyone else who runs into this issue.
Rename `bool::then_*` to `bool::to_option_*` and use where appropriate
Name change following https://github.com/rust-lang/rfcs/pull/2757. Also try it out throughout the compiler in places I think makes the code more readable.
We now only propagate a scalar pair if the Rvalue is a tuple with two
scalars. This for example avoids propagating a (u8, u8) value when
Rvalue has type `((), u8, u8)` (see the regression test). While this is
a correct thing to do, implementation is tricky and will be done later.
Fixes#66971Fixes#66339Fixes#67019
Migrate to LLVM{Get,Set}ValueName2
The deprecated `LLVM{Get,Set}ValueName` only work with NUL-terminated
strings, but the `2` variants use explicit lengths, which fits better
with Rust strings and slices. We now use these in new helper functions
`llvm::{get,set}_value_name` that convert to/from `&[u8]`.
Closes#64223.
r? @rkruppe
SGX: Fix target linker used by bootstrap
Bootstrap, for some reason, overrides the target linker. This is not correct for x86_64-fortanix-unknown-sgx. Add such targets to the list of exceptions.
r? @alexcrichton
Remove potential cfgs duplicates
Fixes https://github.com/rust-lang/rust/issues/66921.
Before going any further (the issue seems to be linked to metadata as far as I can tell). Do you think this is the good place to do it or should it be done before?
r? @eddyb
As discussed in https://github.com/rust-lang/rust/issues/10184
Currently, casting a floating point number to an integer with `as` is Undefined Behavior if the value is out of range. `-Z saturating-float-casts` fixes this soundness hole by making `as` “saturate” to the maximum or minimum value of the integer type (or zero for `NaN`), but has measurable negative performance impact in some benchmarks. There is some consensus in that thread for enabling saturation by default anyway, but provide an `unsafe fn` alternative for users who know through some other mean that their values are in range.
