Do not assume libunwind.a is available on musl
Fixes#40113, #44069, and clux/muslrust#16.
libunwind.a is not copied from musl_root, so it must be integrated into the unwind crate.
Speed up APFloat division by using short division for small divisors.
Fixes#43828 (hopefully), by not doing long division bit-by-bit for small divisors.
When parsing the ~200,000 decimal float literals in the `tuple-stress` benchmark, this change brings roughly a 5x speed increase (from `0.6s` to `0.12s`), and the hottest instructions are native `div`s.
Profile queries
This PR implements the "profile queries" debugging feature described here:
https://github.com/rust-lang-nursery/rust-forge/blob/master/profile-queries.md
In particular, it implements the debugging flag `-Z profile-queries`
FYI: This PR is my second attempt at pushing these changes. My original PR required a rebase; I have now done that rebase manually, after messing up with git's "interactive" rebase support. The original (now closed/cancelled) PR is this one: https://github.com/rust-lang/rust/issues/43156
r? @nikomatsakis
L4Re Target: Add the needed Libraries and locate them
Add the libraries and objects that have to be linked to a get working L4Re Binary using pre- and post-link-args. Additionaly some ld commands had to be passed.
* L4Re libraries and objects will be located by an environment variable.
* gcc libraries and objects will be located using a gcc call.
GCC is mandatory for this target, that might need documentation somewhere. As soon as something mandatory cannot be found, the compiler will panic. This is intended, because the functions involved don't allow the usage of a Result type. libgcc_eh is now passed using `-l` and crtbeginT.o and crtend.o are now located using `gcc -print-filename`.
Implement From<&[T]> and others for Arc/Rc (RFC 1845)
* Implements `From<`{`&[T]`, `&str`, `String`, `Box<T> where T: ?Sized`, `Vec<T>`}`>` for `Arc`/`Rc`
* Removes `rustc_private`-marked methods `Rc::__from_array` and `Rc::__from_str`, replacing their use with `Rc::from`
Tracking issue: #40475
Clarify windows build instructions in README
The old wording made me think you were supposed to do `python x.py --build=msvc`, which is not the case. Specify that you need to use the target triple.
Mention null_mut on the pointer primitive docs.
Also adds a few mentions that both `*const` and `*mut` support functions, when only `*const` was mentioned before.
libproc_macro docs: fix brace and bracket mixup
The documentation indicates that brace is `[`.
Brace is mapped token::Brace which (expectedly) is `{`.
So the documentation is simply confusing brace and bracket there.
Even though it's just a very small issue, it can lead to quite some confusion.
Redox: correct is_absolute() and has_root()
This is awkward, but representing schemes properly in `Components` is not easily possible without breaking backwards compatibility, as discussed earlier in https://github.com/rust-lang/rust/pull/37702.
But these methods can be corrected anyway.
Point "deref coercions" links to new book
Currently the link on doc.rust-lang.org is semi-broken; it links to a page that links to the exact page in the first edition in the book, or to the index of the second edition of the book. If the second editions
is the recommended one now, we should point the links at that one. (In the mean time, the links have been updated to point directly to the first edition of the book, but that hasn't made it onto
the stable channel yet.) By the time this commit makes it onto the stable channel, the second edition of the book should be complete enough. At least the part about deref coercions is.
r? @steveklabnik
Support dynamically-linked and/or native musl targets
These changes allow native compilation on musl-based distributions and the use of dynamic libraries on linux-musl targets. This is intended to remove limitations based on past assumptions about musl targets, while maintaining existing behavior by default.
A minor related bugfix is included.
std: Respect formatting flags for str-like OsStr
Historically many `Display` and `Debug` implementations for `OsStr`-like
abstractions have gone through `String::from_utf8_lossy`, but this was updated
in #42613 to use an internal `Utf8Lossy` abstraction instead. This had the
unfortunate side effect of causing a regression (#43765) in code which relied on
these `fmt` trait implementations respecting the various formatting flags
specified.
This commit opportunistically adds back interpretation of formatting trait flags
in the "common case" where where `OsStr`-like "thing" is all valid utf-8 and can
delegate to the formatting implementation for `str`. This doesn't entirely solve
the regression as non-utf8 paths will format differently than they did before
still (in that they will not respect formatting flags), but this should solve
the regression for all "real world" use cases of paths and such. The door's also
still open for handling these flags in the future!
Closes#43765
Fix logic error in test guarding prototype MIR borrowck code.
Fix logic error in test guarding prototype MIR borrowck code.
tl;dr: 🤦
(This crept in during the shift from a transform to a query (#44009); I didn't notice because my muscle memory was still always passing `-Z mir-borrowck`, while my test cases *also* had the `#[rustc_mir_borrowck]` attribute attached to them.)
Now that musl supports dynamic libraries (although not by default)
enable the tests that now pass. Additional currently-ignored tests
will pass if rustc is built with crt_static=false in config.toml.
Use libgcc_s when linking dynamically. Convert the static libunwind to
static-nobundle, as libunwind.a is copied from musl_root and available
in the library search path.
Static PIE support, while supported on musl, requires a patch to GCC.
Until/unless it is merged, adding '-pie' to the linker command line will
override '-static' and create a binary that requires a dynamic
interpreter (ld.so).
Most UNIX-like platforms do not allow shared libraries to statically
link their own libc, as libc expects to have consistent process-global
state. On those platforms, when we do not have a shared libc available,
we must not attempt to link dylibs or cdylibs. On Windows, however, it
is expected to statically link the CRT into dynamic libraries.
This feature is only relevant for targets that support both fully-static
and fully-dynamic linkage, such as musl on Linux.
This feature allows targets to opt in to full support of the crt-static
feature. Currently, crt-static is allowed on all targets, even those
that really can't or really shouldn't support it. This works because it
is very loose in the specification of its effects. Changing the behavior
of crt-static to be more strict in how it chooses libraries and links
executables would likely cause compilation to fail on these platforms.
To avoid breaking existing uses of crt-static, whitelist targets that
support the new, stricter behavior. For all other targets, this changes
crt-static from being "mostly a no-op" to "explicitly a no-op".
This controls the value of the crt-static feature used when building the
standard library for a target, as well as the compiler itself when that
target is the host.
They are required for linking it, even though it is a library, because
crtn.o in post_link_objects, as hardcoded in src/librustc_back/target/
linux_musl_base.rs, is added to the linker command line for both
executables and libraries.
The old wording made me think you were supposed to do `python x.py --build=msvc`, which is not the case. Specify that you need to use the target triple.