In removing many fields from the crate map, executables no longer always have an
explicit dependency on all upstream libraries. This means that the linker is no
longer picking them up as it used to.
To the best of my knowledge, the current situation is happening:
* On linux, we're passing the --as-needed flag to the linker, meaning that
libraries are stripped out if there are no references to symbols in them.
* Executables may not reference libstd at all, such as "fn main() {}"
* When linking, the linker will discard libstd because there are no references
to symbols in it. I presume that this means that all previous libs have had
all their symbols resolved, so none of the libs are pulling in libstd as a
dependency.
* The only real dependence on libstd comes from the rust_stack_exhausted symbol
(which comes from libmorestack), but -lmorestack is at the end so by the time
this comes up libstd is completely gone, leading to undefined references to
rust_stack_exhausted
I'm not entirely convinced that this is what's happening, but it appears to be
along these lines. The one thing that I'm sure of is that removing the crate map
(and hence implicit dependency on all upstream libraries) has changed how
objects depend on upstream libraries.
This commit moves all logging out of the standard library into an external
crate. This crate is the new crate which is responsible for all logging macros
and logging implementation. A few reasons for this change are:
* The crate map has always been a bit of a code smell among rust programs. It
has difficulty being loaded on almost all platforms, and it's used almost
exclusively for logging and only logging. Removing the crate map is one of the
end goals of this movement.
* The compiler has a fair bit of special support for logging. It has the
__log_level() expression as well as generating a global word per module
specifying the log level. This is unfairly favoring the built-in logging
system, and is much better done purely in libraries instead of the compiler
itself.
* Initialization of logging is much easier to do if there is no reliance on a
magical crate map being available to set module log levels.
* If the logging library can be written outside of the standard library, there's
no reason that it shouldn't be. It's likely that we're not going to build the
highest quality logging library of all time, so third-party libraries should
be able to provide just as high-quality logging systems as the default one
provided in the rust distribution.
With a migration such as this, the change does not come for free. There are some
subtle changes in the behavior of liblog vs the previous logging macros:
* The core change of this migration is that there is no longer a physical
log-level per module. This concept is still emulated (it is quite useful), but
there is now only a global log level, not a local one. This global log level
is a reflection of the maximum of all log levels specified. The previously
generated logging code looked like:
if specified_level <= __module_log_level() {
println!(...)
}
The newly generated code looks like:
if specified_level <= ::log::LOG_LEVEL {
if ::log::module_enabled(module_path!()) {
println!(...)
}
}
Notably, the first layer of checking is still intended to be "super fast" in
that it's just a load of a global word and a compare. The second layer of
checking is executed to determine if the current module does indeed have
logging turned on.
This means that if any module has a debug log level turned on, all modules
with debug log levels get a little bit slower (they all do more expensive
dynamic checks to determine if they're turned on or not).
Semantically, this migration brings no change in this respect, but
runtime-wise, this will have a perf impact on some code.
* A `RUST_LOG=::help` directive will no longer print out a list of all modules
that can be logged. This is because the crate map will no longer specify the
log levels of all modules, so the list of modules is not known. Additionally,
warnings can no longer be provided if a malformed logging directive was
supplied.
The new "hello world" for logging looks like:
#[phase(syntax, link)]
extern crate log;
fn main() {
debug!("Hello, world!");
}
This commit shreds all remnants of libextra from the compiler and standard
distribution. Two modules, c_vec/tempfile, were moved into libstd after some
cleanup, and the other modules were moved to separate crates as seen fit.
Closes#8784Closes#12413Closes#12576
This commit shreds all remnants of libextra from the compiler and standard
distribution. Two modules, c_vec/tempfile, were moved into libstd after some
cleanup, and the other modules were moved to separate crates as seen fit.
Closes#8784Closes#12413Closes#12576
* `Ord` inherits from `Eq`
* `TotalOrd` inherits from `TotalEq`
* `TotalOrd` inherits from `Ord`
* `TotalEq` inherits from `Eq`
This is a partial implementation of #12517.
On Windows, `LLVMRustGetLastError()` may return non-utf8 mojibake string
if system uses non-English locale. It caused ICE when llvm fails.
This patch doesn't fix the real problem, but just make rustc not die.
On Windows, `LLVMRustGetLastError()` may return non-utf8 mojibake string
if system uses non-English locale. It caused ICE when llvm fails.
This patch doesn't fix the real problem, but just make rustc not die.
Formatting via reflection has been a little questionable for some time now, and
it's a little unfortunate that one of the standard macros will silently use
reflection when you weren't expecting it. This adds small bits of code bloat to
libraries, as well as not always being necessary. In light of this information,
this commit switches assert_eq!() to using {} in the error message instead of
{:?}.
In updating existing code, there were a few error cases that I encountered:
* It's impossible to define Show for [T, ..N]. I think DST will alleviate this
because we can define Show for [T].
* A few types here and there just needed a #[deriving(Show)]
* Type parameters needed a Show bound, I often moved this to `assert!(a == b)`
* `Path` doesn't implement `Show`, so assert_eq!() cannot be used on two paths.
I don't think this is much of a regression though because {:?} on paths looks
awful (it's a byte array).
Concretely speaking, this shaved 10K off a 656K binary. Not a lot, but sometime
significant for smaller binaries.
This new SVH is used to uniquely identify all crates as a snapshot in time of
their ABI/API/publicly reachable state. This current calculation is just a hash
of the entire crate's AST. This is obviously incorrect, but it is currently the
reality for today.
This change threads through the new Svh structure which originates from crate
dependencies. The concept of crate id hash is preserved to provide efficient
matching on filenames for crate loading. The inspected hash once crate metadata
is opened has been changed to use the new Svh.
The goal of this hash is to identify when upstream crates have changed but
downstream crates have not been recompiled. This will prevent the def-id drift
problem where upstream crates were recompiled, thereby changing their metadata,
but downstream crates were not recompiled.
In the future this hash can be expanded to exclude contents of the AST like doc
comments, but limitations in the compiler prevent this change from being made at
this time.
Closes#10207
With linkers on unix systems, libraries on the right of the command line are
used to resolve symbols in those on the left of the command line. This means
that arguments must have a right-to-left dependency chain (things on the left
depend on things on the right).
This is currently done by ordering the linker arguments as
1. Local object
2. Local native libraries
3. Upstream rust libraries
4. Upstream native libraries
This commit swaps the order of 2 and 3 so upstream rust libraries have access to
local native libraries. It has been seen that some upstream crates don't specify
the library that they link to because the name varies per platform (e.g.
lua/glfw/etc).
This commit enables building these libraries by allowing the upstream rust crate
to have access to local native libraries. I believe that the failure mode for
this scheme is when an upstream rust crate depends on a symbol in an upstream
library which is then redefined in a local library. This failure mode is
incredibly uncommon, and the failure mode also varies per platform (OSX behaves
differently), so I believe that a change like this is fine to make.
Closes#12446
Commits for details. Highlights:
- `flate` returns `CVec<u8>` to save reallocating a whole new `&[u8]`
- a lot of `transmute`s removed outright or replaced with `as` (etc.)
The std::run module is a relic from a standard library long since past, and
there's not much use to having two modules to execute processes with where one
is slightly more convenient. This commit merges the two modules, moving lots of
functionality from std::run into std::io::process and then deleting
std::run.
New things you can find in std::io::process are:
* Process::new() now only takes prog/args
* Process::configure() takes a ProcessConfig
* Process::status() is the same as run::process_status
* Process::output() is the same as run::process_output
* I/O for spawned tasks is now defaulted to captured in pipes instead of ignored
* Process::kill() was added (plus an associated green/native implementation)
* Process::wait_with_output() is the same as the old finish_with_output()
* destroy() is now signal_exit()
* force_destroy() is now signal_kill()
Closes#2625Closes#10016
This trades an O(n) allocation + memcpy for a O(1) proc allocation (for
the destructor). Most users only need &[u8] anyway (all of the users in
the main repo), and so this offers large gains.
With the stability attributes we can put public-but unstable modules next to others, so this moves `intrinsics` and `raw` out of the `unstable` module (and marks both as `#[experimental]`).
These two containers are indeed collections, so their place is in
libcollections, not in libstd. There will always be a hash map as part of the
standard distribution of Rust, but by moving it out of the standard library it
makes libstd that much more portable to more platforms and environments.
This conveniently also removes the stuttering of 'std::hashmap::HashMap',
although 'collections::HashMap' is only one character shorter.
Two optimizations:
1. Compress `foo.bc` in each rlib with `flate`. These are just taking up space and are only used with LTO, no need for LTO to be speedy.
2. Stop install `librustc.rlib` and friends, this is a *huge* source of bloat. There's no need for us to install static libraries for these components.
cc #12440
Added allow(non_camel_case_types) to librustc where necesary
Tried to fix problems with non_camel_case_types outside rustc
fixed failing tests
Docs updated
Moved #[allow(non_camel_case_types)] a level higher.
markdown.rs reverted
Fixed timer that was failing tests
Fixed another timer
This "bubble up an error" macro was originally named if_ok! in order to get it
landed, but after the fact it was discovered that this name is not exactly
desirable.
The name `if_ok!` isn't immediately clear that is has much to do with error
handling, and it doesn't look fantastic in all contexts (if if_ok!(...) {}). In
general, the agreed opinion about `if_ok!` is that is came in as subpar.
The name `try!` is more invocative of error handling, it's shorter by 2 letters,
and it looks fitting in almost all circumstances. One concern about the word
`try!` is that it's too invocative of exceptions, but the belief is that this
will be overcome with documentation and examples.
Close#12037
The new methodology can be found in the re-worded comment, but the gist of it is
that -C prefer-dynamic doesn't turn off static linkage. The error messages
should also be a little more sane now.
Closes#12133
The new methodology can be found in the re-worded comment, but the gist of it is
that -C prefer-dynamic doesn't turn off static linkage. The error messages
should also be a little more sane now.
Closes#12133
When creating a staticlib, it unzips all static archives it finds and then
inserts the files manually into the output file. This process is done through
`ar`, and `ar` doesn't like if you specify you want to add files and you don't
give it any files.
This case arose whenever you linked to an archive that didn't have any contents
or all of the contents were filtered out. This just involved ignoring the case
where the number of inputs we have is 0, because we don't have any files to add
anyway.
This will hopefully bring us closer to #11937. We're still using gcc's idea of
"startup files", but this should prevent us from leaking in dependencies that we
don't quite want (libgcc for example once compiler-rt is what we use).
This will hopefully bring us closer to #11937. We're still using gcc's idea of
"startup files", but this should prevent us from leaking in dependencies that we
don't quite want (libgcc for example once compiler-rt is what we use).
Includes an upstream commit by pcwalton to improve codegen of our enums getting
moved around.
This also introduces a new commit on top of our stack of patches to fix a mingw32 build issue. I have submitted the patch upstream: http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20140210/204653.html
I verified that this builds on the try bots, which amazes me because I think that c++11 is turned on now, but I guess we're still lucky!
Closes#10613 (pcwalton's patch landed)
Closes#11992 (llvm has removed these options)
This is an attempt to remove some more of Rust's dependencies on libgcc and replace it with LLVM's compiler-rt lib. I've added compiler-rt as a submodule and changed libstd to link with it.
As far as I could verify, after this change, the only symbols still imported by std from libgcc are the stack unwinding functions. Other crates, however, still picked up symbols from libgcc, not from libstd, as I had hoped. So linking definitely requires some work.
I've only tested this on windows, 32-bit linux and android and fully expect it to fail on other platforms. Patches are welcome.
