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
The changes are basically just because rustdoc runs tests/rendering on
more snippets by default (i.e. everything without a `notrust` tag), and
not anything significant.
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.
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
Part of #8784
Changes:
- Everything labeled under collections in libextra has been moved into a new crate 'libcollection'.
- Renamed container.rs to deque.rs, since it was no longer 'container traits for extra', just a deque trait.
- Crates that depend on the collections have been updated and dependencies sorted.
- I think I changed all the imports in the tests to make sure it works. I'm not entirely sure, as near the end of the tests there was yet another `use` that I forgot to change, and when I went to try again, it started rebuilding everything, which I don't currently have time for.
There will probably be incompatibility between this and the other pull requests that are splitting up libextra. I'm happy to rebase once those have been merged.
The tests I didn't get to run should pass. But I can redo them another time if they don't.
This commit removes the -c, --emit-llvm, -s, --rlib, --dylib, --staticlib,
--lib, and --bin flags from rustc, adding the following flags:
* --emit=[asm,ir,bc,obj,link]
* --crate-type=[dylib,rlib,staticlib,bin,lib]
The -o option has also been redefined to be used for *all* flavors of outputs.
This means that we no longer ignore it for libraries. The --out-dir remains the
same as before.
The new logic for files that rustc emits is as follows:
1. Output types are dictated by the --emit flag. The default value is
--emit=link, and this option can be passed multiple times and have all
options stacked on one another.
2. Crate types are dictated by the --crate-type flag and the #[crate_type]
attribute. The flags can be passed many times and stack with the crate
attribute.
3. If the -o flag is specified, and only one output type is specified, the
output will be emitted at this location. If more than one output type is
specified, then the filename of -o is ignored, and all output goes in the
directory that -o specifies. The -o option always ignores the --out-dir
option.
4. If the --out-dir flag is specified, all output goes in this directory.
5. If -o and --out-dir are both not present, all output goes in the current
directory of the process.
6. When multiple output types are specified, the filestem of all output is the
same as the name of the CrateId (derived from a crate attribute or from the
filestem of the crate file).
Closes#7791Closes#11056Closes#11667
