book/ffi: nullable pointer cleanup
Expand the "nullable pointer optimization" section with a code example. Fixes#34250.
I also noticed that many of the examples use the libc crate just for types such as `c_char` and `c_int`, which are now available through `std::os::raw`. I changed the ones that don't need to rely on libc. I'm glad to revert that part of the commit if it's unwanted churn.
We don't actually officially support this at all, and the execution engine
support in LLVM we've had to gut as it's not compiling on MinGW, so just delete
this test for now.
Previously the C type LLVMRelocMode (available as RelocMode in Rust)
was passed as is to the function.
However createTargetMachine expects a Reloc::Model, which is an enum
just one value short.
Additionally, the function was marked as requiring Reloc::Model in the
C code, but RelocMode on the Rust-side.
We now use the correct C type LLVMRelocMode and convert it to an
Optional<Reloc::Model> as expected by the createTargetMachine call the
same the original LLVMCreateTargetMachine function does.
See
c9b262bfbd/lib/Target/TargetMachineC.cpp (L104-L121)
This was found by @eddyb.
Since LLVM reversed the order of the debug info graphs, we need to have
a compile unit that exists *before* any functions (`DISubprogram`s) are
created. This allows the LLVM debug info builder to automatically link
the functions to the compile unit.
Convert built-in targets to JSON
Convert the built-in targets to JSON to ensure that the JSON parser is always fully featured. This follows on #32988 and #32847. The PR includes a number of extra commits that are just intermediate changes necessary for bisectibility and the ability to prove correctness of the change.
Enable reuse of `.o` files if nothing has changed
This PR completes a first "spike" for incremental compilation by enabling us to reuse `.o` files when nothing has changed. When in incr. mode, we will save `.o` files into the temporary directory, then copy them back out again if they are still valid. The code is still a bit rough but it does seem to work. =)
r? @michaelwoerister
Fixes#34036Fixes#34037Fixes#34038
Escape fewer Unicode codepoints in `Debug` impl of `str`
Use the same procedure as Python to determine whether a character is
printable, described in [PEP 3138]. In particular, this means that the
following character classes are escaped:
- Cc (Other, Control)
- Cf (Other, Format)
- Cs (Other, Surrogate), even though they can't appear in Rust strings
- Co (Other, Private Use)
- Cn (Other, Not Assigned)
- Zl (Separator, Line)
- Zp (Separator, Paragraph)
- Zs (Separator, Space), except for the ASCII space `' '` `0x20`
This allows for user-friendly inspection of strings that are not
English (e.g. compare `"\u{e9}\u{e8}\u{ea}"` to `"éèê"`).
Fixes#34318.
CC #34422.
[PEP 3138]: https://www.python.org/dev/peps/pep-3138/
This reverts commit f7019a4e2f.
This removed the only way to make a suggestion with more than one
substitute. Bring it back until we come up with a better solution.
