First step towards #10634.
Treating stub files as C++ allows to use zig c++ as a host
compiler for nvcc.
Treating cu files as C++ allow using zig c++ as a host compiler in
CMake. CMake calls the host compiler with -E on a cu file to identify
the compiler.
Using zig c++ to directly compile CUDA code is untested.
This is only relevant for ELF files.
I also fixed a bug where passing a zig source file to `zig cc` would
incorrectly punt to clang because it thought there were no positional
arguments.
Prior to this change, `__DATA,__bss` and `__DATA,__thread_bss` would
get actually, physically written out to the output file, unnecessarily
filling the output file with 0s.
This was originally introduced in 4d48948b526337947ef59a83f7dbc81b70aa5723
but broken immediately afterwards in c8af00c66e8b6f62e4dd6ac4d86a3de03e9ea354.
* Fix incorrect result when the first digit after the decimal point is not 0-9 - eg 0x0.ap0
* Fix compiler panic when the number starts with `0X` with a capital `X` - eg 0X0p0
* Fix compiler panic when the number has a decimal point immediately after `0x` - eg 0x.0p0
Prior to this change, even if the use specified the sysroot on the
compiler line like so
```
zig cc --sysroot=/path/to/sdk
```
it would only be used as a prefix to include paths and not as a prefix
for `zig ld` linker.
- Add an `Metadata.isFree` helper method.
- Implement `Metadata.isTombstone` and `Metadata.isFree` with `@bitCast` then comparing to a constant. I assume `@bitCast`-then-compare is faster than the old method because it only involves one comparison, and doesn't require bitmasking.
- Summary of benchmarked changes (`gotta-go-fast`, run locally, compared to master):
- 3/4 of the hash map benchmarks used ~10% fewer cycles
- The last one (project Euler) shows 4% fewer cycles.
copy_cqes() is not guaranteed to return as many CQEs as provided in the
`wait_nr` argument, meaning the assert in `copy_cqe` can trigger.
Instead, loop until we do get at least one CQE returned.
This mimics the behaviour of liburing's _io_uring_get_cqe.
This saves on comptime format string parsing, as the compiler caches
comptime calls. The catch here, is that parsePlaceHolder cannot take the
placeholder string as a slice. It must take it as an array by value for
the caching to occure.
There is also some logic in here that ensures that the specifier_arg is
always them same slice when the items they contain are the same. This
makes the compiler stamp out less copies of formatType.
