Now that MSVC support has landed in the most recent nightlies we can now have
MSVC bootstrap itself without going through a GNU compiler first. Unfortunately,
however, the bootstrap currently fails due to the compiler not being able to
find the llvm-ar.exe tool during the stage0 libcore compile. The compiler cannot
find this tool because it's looking inside a directory that does not exist:
$SYSROOT/rustlib/x86_64-pc-windows-gnu/bin
The `gnu` on this triple is because the bootstrap compiler's host architecture
is GNU. The build system, however, only arranges for the llvm-ar.exe tool to be
available in this location:
$SYSROOT/rustlib/x86_64-pc-windows-msvc/bin
To resolve this discrepancy, the build system has been modified to understand
triples that are bootstrapped from another triple, and in this case copy the
native tools to the right location.
Windows tests can often deadlock if a child thread continues after the main
thread and then panics, and a `println!` executed in a child thread after the
main thread has exited is at risk of panicking.
Currently, there are two conditional blocks that exist to check for "clang or gcc"
On line 866:
```
if [ -z "$CFG_ENABLE_CLANG" -a -z "$CFG_GCC" ]
then
err "either clang or gcc is required"
fi
```
and on line 1019:
```
if [ -z "$CC" -a -z "$CFG_ENABLE_CLANG" -a -z "$CFG_GCC" ]
then
err "either clang or gcc is required"
fi
```
Given the order of the clauses, this results in the "either clang or gcc is required" error from the earlier block, (even) when CC is set.
The expected behaviour is to honour user-flags, in this case CC.
Aside from removing all hand-holdy compiler checks in favour of actual compiler *feature* checks, this change removes the redundant former block in favour of the latter block, which appears designed to allow the expected behaviour.
The changes scaled back in 4cc025d8 were a little too aggressive and broke a
bunch of cross compilations by not defining the `LINK_$(1)` variable for all
targets. This commit ensures that the variable is defined for all targets by
defaulting it to the normal compiler if it's not already defined (it's only
defined specially for MSVC).
Closes#25723Closes#25802
Windows tests can often deadlock if a child thread continues after the main
thread and then panics, and a `println!` executed in a child thread after the
main thread has exited is at risk of panicking.
The current codegen tests only compare IR line counts between similar
rust and C programs, the latter getting compiled with clang. That looked
like a good idea back then, but actually things like lifetime intrinsics
mean that less IR isn't always better, so the metric isn't really
helpful.
Instead, we can start doing tests that check specific aspects of the
generated IR, like attributes or metadata. To do that, we can use LLVM's
FileCheck tool which has a number of useful features for such tests.
To start off, I created some tests for a few things that were recently
added and/or broken.
The current codegen tests only compare IR line counts between similar
rust and C programs, the latter getting compiled with clang. That looked
like a good idea back then, but actually things like lifetime intrinsics
mean that less IR isn't always better, so the metric isn't really
helpful.
Instead, we can start doing tests that check specific aspects of the
generated IR, like attributes or metadata. To do that, we can use LLVM's
FileCheck tool which has a number of useful features for such tests.
To start off, I created some tests for a few things that were recently
added and/or broken.
Currently, for `use` declarations with multiple paths, only the `use` item itself is saved in the AST map, not the individual path nodes. This can lead to a problem when a span of a specific path node is needed.
For example, #24818 caused an ICE because of this, in `ImportResolver::check_for_conflicting_import()`.
Fixes#25763.
Needed to support:
```rust
match X {
pattern if Y ...
}
for pattern in Y {}
```
IMO, this shouldn't require an RFC because it can't interfere with any future language changes (because `pattern if` and `pattern in` are already legal in rust) and can't cause any ambiguity.
- Adds explanations for E0055, E0089, E0192, E0261-E0263, E0318
- Improves explanations for E0250, E0368, E0372.
- Converts 15 diagnostics to have error codes (E0380-E0394). Adds an explanation for E0380.
- The E0087-E0090 messages currently look like "expected {} parameter(s) found {} parameter(s)". This changes them to either use "parameter" or "parameters", based on the number.
This is, in part, more progress towards #24407
