- Correctly categorize env pointer deref for `FnMut` as declared
rather than inherited. This fixes an assert in borrowck.
Closes#18238
- Categorize env pointer deref as mutable only if the closure is
`FnMut` *and* the original variable is declared mutable. This
disallows capture-by-value `FnMut` closures from mutating captured
variables that aren't declared mutable. This is a difference
from the equivalent desugared code which would permit it, but
it is consistent with the behavior of procs. Closes#18335
- Avoid computing info about the env pointer if there isn't one.
The real size is also more useful than just a boolean, and the caller
can easily determine if the operation failed from the real size. In most
cases, the caller is only going to be growing the allocation so a branch
can be avoided.
[breaking-change]
The C standard library functions should be used directly. The quirky
NULL / zero-size allocation workaround is no longer necessary and was
adding an extra branch to the allocator code path in a build without
jemalloc. This is a small step towards liballoc being compatible with
handling OOM errors instead of aborting (#18292).
[breaking-change]
With MIN_ALIGN as a static, other crates don't have access to its value
at compile time, because it is an extern global. That means that the
checks against it can't be optimized out, which is rather unfortunate.
So let's make it a constant instead.
Explain the primary disadvantage of garbage collection is runtime
overhead and unpredictable pauses. Elucidate where the name "race
condition" comes from. Emphasize that Rust can guarantee your code is
free of race conditions and other memory errors, with no runtime
overhead.
cc @steveklabnik
Rather than doing it top-down, with a known expected type, we will now simply establish the appropriate constraints between the pattern and the expression it destructures.
Closes#8783.
Closes#10200.
Adds an `assume` intrinsic that gets translated to llvm.assume. It is
used on a boolean expression and allows the optimizer to assume that
the expression is true.
This implements #18051.
Instead of checking patterns in a top-down fashion with a known
expected type on entry, this changes makes typeck establish
appropriate constraints between a pattern and the expression
it destructures, and lets inference compute the final types
or produce good error messages if it's impossible.
This installs signal handlers to print out stack overflow messages on Linux. It also ensures the main thread has a guard page.
This will catch stack overflows in external code. It's done in preparation of switching to stack probes (#16012).
I've done some simple tests with overflowing the main thread, native threads and green threads (with and without UV) on x86-64.
This might work on ARM, MIPS and x86-32.
I've been unable to run the test suite on this because of #16305.
Closes#17075
I don't know if this is correct. The easiest way to find out is to run the following program on all targets but I can't do it myself.
```c
#include <stdint.h>
#include <stdio.h>
int main(void)
{
if (sizeof(intmax_t) != 8) {
puts("ERROR");
return 1;
}
}
```
Old vs. New vs. Vec::push_all
```
test slice ... bench: 3091942 ns/iter (+/- 54460)
test slice_new ... bench: 1800065 ns/iter (+/- 69513)
test vec ... bench: 1804805 ns/iter (+/- 75609)
```
The variable name <code>one_to_one_hundred</code> implies that it will contain a collection with the values from 1 to 100, but the collection contains the values from 0 to 99. This patch changes the ranges to produce a collection with the values from 1 to 100.
Enable parallel codegen (2 units) by default when --opt-level is 0 or 1. This
gives a minor speedup on large crates (~10%), with only a tiny slowdown (~2%)
for small ones (which usually build in under a second regardless). The current
default (no parallelization) is used when the user requests optimization
(--opt-level 2 or 3), and when the user has enabled LTO (which is incompatible
with parallel codegen).
This commit also changes the rust build system to use parallel codegen
when appropriate. This means codegen-units=4 for stage0 always, and
also for stage1 and stage2 when configured with --disable-optimize.
(Other settings use codegen-units=1 for stage1 and stage2, to get
maximum performance for release binaries.) The build system also sets
codegen-units=1 for compiletest tests (compiletest does its own
parallelization) and uses the same setting as stage2 for crate tests.
r? @aturon
