Who would have thought that namespaces are such a can of worms `:P` This is mostly because of some GDB idiosyncrasies (does not use namespace information but linkage-name attributes for displaying items contained in namespaces, also cannot handle functions lexically nested within functions), monomorphization, and information about external items only available from metadata.
This pull request tries to tackle the problem anyway:
* The `DW_AT_linkage_name` for functions is generated just to make GDB display a proper namespace-enabled function name. To this end, a pseudo-mangled name is generated, not corresponding to the real linkage name. This approach shows some success and could be extended to make GDB also show proper parameter types.
* As GDB won't accept subprogram DIEs nested within other subprogram DIEs, the `debuginfo` module now generates a *companion namespace* for each functions (iff needed). A function `fn abc()` will get a companion namespace with name `abc()`, which contains all items (modules, types, functions) declared within the functions scope. The real, proper solution, in my opinion, would be to faithfully reflect the program's lexical structure within DWARF (which allows arbitrary nesting of DIEs, afaik), but I am not sure LLVM's source level debugging implementation would like that and I am pretty sure GDB won't support this in the foreseeable future.
* Monomorphization leads to functions and companion namespaces like `somelib::some_func<int, float>()::some_other_function<bool, bool, bool>()`, which I think is the desired behaviour. There is some design space here, however. Maybe you people prefer `somelib::some_func()::some_other_function<bool, bool, bool>()` or `somelib::some_func()::some_other_function::<int, float, bool, bool, bool>()`.
The solution will work for now but there are a few things on my 'far future wish list':
* A real specification somewhere, what language constructs are mapped to what DWARF structures.
* Proper tests that directly compare the generated DWARF information to the expected results (possibly using something like [pyelftools](https://github.com/eliben/pyelftools) or llvm-dwarfdump)
* A unified implementation for crate-local and crate-external items (which would possibly involve beefing up `ast_map::path` and metadata a bit)
Any comments are welcome!
Closes#1541Closes#1542 (there might be other issues with function name prettiness, but this specific issue should be fixed)
Closes#7715 (source locations for structs and enums are now read correctly from the AST)
Ensures that each AST node has a unique id. Fixes numerous bugs in macro expansion and deriving. Add two
representative tests.
Fixes#7971Fixes#6304Fixes#8367Fixes#8754Fixes#8852Fixes#2543Fixes#7654
has a unique id. Fixes numerous bugs in macro expansion and deriving. Add two
representative tests.
Fixes#7971Fixes#6304Fixes#8367Fixes#8754Fixes#8852Fixes#2543Fixes#7654
Visit the free functions of std::vec and reimplement or remove some. Most prominently, remove `each_permutation` and replace with two iterators, ElementSwaps and Permutations.
Replace unzip, unzip_slice with an updated `unzip` that works with an iterator argument.
Replace each_permutation with a Permutation iterator. The new permutation iterator is more efficient since it uses an algorithm that produces permutations in an order where each is only one element swap apart, including swapping back to the original state with one swap at the end.
Unify the seldomly used functions `build`, `build_sized`, `build_sized_opt` into just one function `build`.
Remove `equal_sizes`
These functions have very few users since they are mostly replaced by
iterator-based constructions.
Convert a few remaining users in-tree, and reduce the number of
functions by basically renaming build_sized_opt to build, and removing
the other two. This for both the vec and the at_vec versions.
The trait will keep the `Iterator` naming, but a more concise module
name makes using the free functions less verbose. The module will define
iterables in addition to iterators, as it deals with iteration in
general.
This removes another large chunk of this odd 'clownshoes' identifier showing up
in symbol names. These all originated from external crates because the encoded
items were encoded independently of the paths calculated in ast_map. The
encoding of these paths now uses the helper function in ast_map to calculate the
"pretty name" for an impl block.
Unfortunately there is still no information about generics in the symbol name,
but it's certainly vastly better than before
hash::__extensions__::write::_version::v0.8
becomes
hash::Writer$SipState::write::hversion::v0.8
This also fixes bugs in which lots of methods would show up as `meth_XXX`, they
now only show up as `meth` and throw some extra characters onto the version
string.
This removes another large chunk of this odd 'clownshoes' identifier showing up
in symbol names. These all originated from external crates because the encoded
items were encoded independently of the paths calculated in ast_map. The
encoding of these paths now uses the helper function in ast_map to calculate the
"pretty name" for an impl block.
Unfortunately there is still no information about generics in the symbol name,
but it's certainly vastly better than before
hash::__extensions__::write::_version::v0.8
becomes
hash::Writer$SipState::write::hversion::v0.8
This also fixes bugs in which lots of methods would show up as `meth_XXX`, they
now only show up as `meth` and throw some extra characters onto the version
string.
These commits fix bugs related to identically named statics in functions of implementations in various situations. The commit messages have most of the information about what bugs are being fixed and why.
As a bonus, while I was messing around with name mangling, I improved the backtraces we'll get in gdb by removing `__extensions__` for the trait/type being implemented and by adding the method name as well. Yay!
Remove __extensions__ from method symbols as well as the meth_XXX. The XXX is
now used to append a few characters at the end of the name of the symbol.
Closes#6602
This is currently unsound since `bool` is represented as `i8`. It will
become sound when `bool` is stored as `i8` but always used as `i1`.
However, the current behaviour will always be identical to `x & 1 != 0`,
so there's no need for it. It's also surprising, since `x != 0` is the
expected behaviour.
Closes#7311
d0a1176 r=huonw
e4a76e6 r=thestinger
This is currently unsound since `bool` is represented as `i8`. It will
become sound when `bool` is stored as `i8` but always used as `i1`.
However, the current behaviour will always be identical to `x & 1 != 0`,
so there's no need for it. It's also surprising, since `x != 0` is the
expected behaviour.
Closes#7311
This pull request includes
* support for variables captured in closures*,
* a fix for issue #8512: arguments of non-immediate type (structs, tuples, etc) passed by value can now be accessed correctly in GDB. (I managed to fix this by using `llvm::DIBuilder::createComplexVariable()`. ~~However, I am not sure if this relies on unstable implementation details of LLVM's debug info handling. I'll try to clarify this on the LLVM mailing list~~).
* simplification of the `debuginfo` module's public interface: the caller of functions like `create_local_var_metadata()` doesn't have to know and catch all cases when it mustn't call the function,
* a cleanup refactoring with unified handling for locals, [self] arguments, captured variables, and match bindings,
* and proper span information for self arguments.
\* However, see comment at 1d916ace13/src/test/debug-info/var-captured-in-nested-closure.rs (L62) . This is the same problem as with the fix for issue #8512 above: We are probably using `llvm.dbg.declare` in an unsupported way that works today but might not work after the next LLVM update.
Cheers,
Michael
Fixes#8512Fixes#1341
Current access methods are nestable and unsafe. This patch renames
current methods implementation - prepends unsafe_ - and implements 2 new
methods that are both safe and un-nestable.
Fixes#7473
Current access methods are nestable and unsafe. This patch renames
current methods implementation - prepends unsafe_ - and implements 2 new
methods that are both safe and un-nestable.
Fixes#7473
Significant progress on #6875, enough that I'll open new bugs and turn that into a metabug when this lands.
Description & example in the commit message.
