- neg can only overflow, if a == MIN
- case `-0` is properly handled by hardware, so overflow check by comparing
`a == MIN` is sufficient
- tests: MIN, MIN+1, MIN+4, -42, -7, -1, 0, 1, 7..
See #1290
* Make bcrypt State struct public
This is useful to implement the various protocols outside of the standard library
* Implement bcrypt pbkdf
This variant is used in e.g. SSH
The OpenBSD implementation was used as a reference
* remove false positive "all prongs handled" compile error for
non-exhaustive enums.
* implement `@TypeInfo` for enums, except enums which have any
declarations is still TODO.
* `getBuiltin` uses nomespaceLookup/analyzeDeclVal rather than
namespaceLookupRef/analyzeLoad. Avoids a detour through an
unnecessary type, and adds a detour through a caching mechanism.
* `Value.eql`: add missing code to handle enum comparisons for
non-exhaustive enums. It works by converting the enum tags to numeric
values and comparing those.
- abs can only overflow, if a == MIN
- comparing the sign change from wrapping addition is branchless
- tests: MIN, MIN+1,..MIN+4, -42, -7, -1, 0, 1, 7..
See #1290
The linker will now emit names for all function, global and data segment symbols.
This increases the ability to debug wasm modules tremendously as tools like wasm2wat
can use this information to generate named functions, globals etc, rather than placeholders such as $f1.
The self-hosted compiler cannot yet deal with the print function that this
field enables. It is not critical, however, and allows us to remove formatting
from the list of neccesary features to implement to get the page allocator
working.
Make `@returnAddress()` return for the BPF target, as the BPF target for
the time being does not support probing for the return address. Stack
traces for the general purpose allocator for the BPF target is also set
to not be captured.
Before, `std.Progress` was printing unwanted stuff to stderr. Now, the
test runner's logic to detect whether we should print each test as a
separate line to stderr is properly activated.
The status quo for the `build.zig` build system is preserved in
the sense that, if the user does not explicitly override
`dylib.setInstallName(...);` in their build script, the default
of `@rpath/libname.dylib` applies. However, should they want to
override the default behaviour, they can either:
1) unset it with
```dylib.setIntallName(null);```
2) set it to an explicit string with
```dylib.setInstallName("somename.dylib");```
When it comes to the command line however, the default is not to
use `@rpath` for the install name when creating a dylib. The user
will now be required to explicitly specify the `@rpath` as part
of the desired install name should they choose so like so:
1) with `build-lib`
```
zig build-lib -dynamic foo.zig -install_name @rpath/libfoo.dylib
```
2) with `cc`
```
zig cc -shared foo.c -o libfoo.dylib -Wl,"-install_name=@rpath/libfoo.dylib"
```
This reverts commit 11803a3a569205d640c7ec0b0aedba83f47a6e64.
Observations from the performance dashboard:
* strictly worse in terms of CPU instructions
* slightly worse wall time (but this can be noisy)
* sometimes better, sometimes worse for branch predictions
Given that the commit was introducing complexity for optimization's
sake, these performance changes do not seem worth it.
See https://github.com/ziglang/zig/pull/10337 for context.
In #10337 the `available` tracking fix necessitated an additional condition on the probe loop in both `getOrPut` and `getIndex` to prevent an infinite loop. Previously, this condition was implicit thanks to the guaranteed presence of a free slot.
The new condition hurts the `HashMap` benchmarks (https://github.com/ziglang/zig/pull/10337#issuecomment-996432758).
This commit removes that extra condition on the loop. Instead, when probing, first check whether the "home" slot is the target key — if so, return it. Otherwise, save the home slot's metadata to the stack and temporarily "free" the slot (but don't touch its value). Then continue with the original loop. Once again, the loop will be implicitly broken by the new "free" slot. The original metadata is restored before the function returns.
`getOrPut` has one additional gotcha — if the home slot is a tombstone and `getOrPut` misses, then the home slot is is written with the new key; that is, its original metadata (the tombstone) is not restored.
Other changes:
- Test hash map misses.
- Test using `getOrPutAssumeCapacity` to get keys at the end (along with `get`).
When entries are inserted and removed into a hash map at an equivalent rate (maintaining a mostly-consistent total count of entries), it should never need to be resized. But `HashMapUnmanaged.available` does not presently count tombstoned slots as "available", so this put/remove pattern eventually panics (assertion failure) when `available` reaches `0`.
The solution implemented here is to count tombstoned slots as "available". Another approach (which hashbrown (b3eaf32e60/src/raw/mod.rs (L1455-L1542)) takes) would be to rehash all entries in place when there are too many tombstones. This is more complex but avoids an `O(n)` bad case when the hash map is full of many tombstones.
This number tracks the glibc version in the oldest still-active LTS
version of Debian, which is Jessie, extended LTS expiring in June 2022,
at which point this number can be bumped again.
execve can return EBADLIB on Linux. I observed this when passing
an x86_64 interpreter path to qemu-i386.
This error code is Linux and Solaris-only. I came up with an improved
pattern for dealing with OS-specific error codes.
Since `BoundedArray.insert` internally reserves space for the element
to be inserted, it can support inserting at the position that is
the current length of the array. Change the check for the insertion position
to allow this.
- adds __cmpsi2, __cmpdi2, __cmpti2
- adds __ucmpsi2, __ucmpdi2, __ucmpti2
- use 2 if statements with 2 temporaries and a constant
- tests: MIN, MIN+1, MIN/2, -1, 0, 1, MAX/2, MAX-1, MAX if applicable
See #1290
- use negXi2.zig to prevent confusion with negXf2.zig
- used for size optimized builds and machines without carry instruction
- tests: special cases 0, -INT_MIN
* use divTrunc range and shift with constant offsets
See #1290
Notating a symbol to be exported in code will only tell the linker
where to find this symbol, so other object files can find it. However, this does not mean
said symbol will also be exported to the host environment. Currently, we 'fix' this by force
exporting every single symbol that is visible. This creates bigger binaries and means host environments
have access to symbols that they perhaps shouldn't have. Now, users can tell Zig which symbols
are to be exported, meaning all other symbols that are not specified will not be exported.
Another change is we now support `-rdynamic` in the wasm linker as well, meaning all symbols will
be put in the dynamic symbol table. This is the same behavior as with ELF. This means there's a 3rd strategy
users will have to build their wasm binary.
When the Zig compiler is statically linked, it inspects the
/usr/bin/env ELF file to determine the native glibc version, by checking
the DT_RUNPATH, and then calling readlink() on the libc.so file, because
typically the symlink will have e.g. libc-2.33.so in the name, revealing
the glibc version.
Fortunately, this information is also in readlink() of ld.so, which is
available as the "INTERP" file path. This commit looks for e.g.
`ld-2.33.so` on the symlink data for the dynamic linker.
In theory a more complete solution would also look at `/etc/ld.so.cache`
if necessary, and finally fall back to some hard coded paths, in order
to resolve the location of libc.so, in order to do this readlink() trick
on the resulting path. You can find that flow chart with `man ld.so`.
But I think this logic will be enough to get a correct answer in all real
world cases.
This has been tested on Debian Buster and glibc-based Void Linux.
Fixes#6469
