Both Clang and GCC support using multiple threads for preforming link
time optimizaions, and they can now be configured using the
`-Db_lto_threads` option.
Fixes#7820
I would have prefered to do these seperatately, but they are combined in
some cases, so it was much easier to convert them together.
this eliminates the builtins_per_machine dict, as it's duplicated with
the OptionKey's machine parameter.
We do this by making the mixins inherit the Compiler class only when
mypy is examining the code (using some clever inheritance shenanigans).
This caught a bunch of issues, and also lets us delete a ton of code.
Meson calls `path/to/clang++ --version` to guess which build toolchain the
user has picked to build the source code. For the Qualcomm LLVM toolchain,
the output have an unusual output as shown below:
```
clang version 8.0.12
Snapdragon LLVM ARM Compiler 8.0.12 (based on llvm.org 7.0+)
Target: arm-unknown-linux-gnueabi
Thread model: posix
Repository: (ssh://git-hexagon-aus.qualcomm.com:...)
InstalledDir: /pkg/qct/software/llvm/release/arm/8.0.12/bin
```
Another unusual pattern is the output of `path/to/ld.qcld --version`:
```
ARM Linker from Snapdragon LLVM ARM Compiler Version 8.0.12
ARM Linker based on LLVM version: 8.0
```
The Meson logic is modified accordingly so that Meson can correctly
determine toolchain as "LLVM aarch64 cross-compiler on GNU/Linux64 OS".
This is the expected output of
`meson --native-file native_file.ini --cross-file cross_file.ini build/aarch64-debug/`:
```
...
C++ compiler for the host machine: ... (clang 8.0.12 "clang version 8.0.12")
C++ linker for the host machine: ... ld.lld 8.0.12
...
```
Simmilar to gcc, the list of pre-processor defines can be fetched with
`-dM -E` option. The way cpu_family is determined on linux relies on
this list.
Fixes incorrect value of cpu_family on linux, when crosscompiling:
```
CC="clang -m32" meson ./build
```
Signed-off-by: Yevhenii Kolesnikov <yevhenii.kolesnikov@globallogic.com>
Co-authored-by: Dylan Baker <dylan@pnwbakers.com>
D lang compilers have an option -release (or similar) which turns off
asserts, contracts, and other runtime type checking. This patch wires
that up to the b_ndebug flag.
Fixes#7082
Clang supports the GCC -Og flag, but --optimization=g is not setting that. This is because Clang is referencing the clike_optimization_args, which does not define a flag for 'g'.
To address this, we'll mimic the GNU options instead of the C-like ones.
Fixes#6619
Now that the linkers are split out of the compilers this enum is
only used to know what platform we're compiling for. Which is
what the MachineInfo class is for