macOS provides the tool `lipo` to check the archs supported by an
object (executable, static library, dylib, etc). This is especially
useful for fat archives, but it also helps with thin archives.
Without this, the linker will fail to link to the library we mistakenly
'found' like so:
ld: warning: ignoring file /path/to/libfoo.a, missing required architecture armv7 in file /path/to/libfoo.a
Instead of only doing a naive filesystem search, also run the linker
so that it can tell us whether the -F path specified actually contains
the framework we're looking for.
Unfortunately, `extraframework` searching is still not 100% correct in
the case when since we want to search in either /Library/Frameworks or
in /System/Library/Frameworks but not in both. The -Z flag disables
searching in those prefixes and would in theory allow this, but then
you cannot force the linker to look in those by manually adding -F
args, so that doesn't work.
Store the MSVC compiler target architecture ('x86', 'x64' or 'ARM' (this
is ARM64, I believe)), rather than just if it's x64 or not.
The regex used for target architecture should be ok, based on this list
of [1] version outputs, but we assume x86 if no match, for safety's
sake.
[1] https://stackoverflow.com/a/1233332/1951600
Also detect arch even if cl outputs version to stdout.
Ditto for clang-cl
Future work: is_64 is now only used in get_instruction_set_args()
This allows each implementation (gnu-like) and msvc to be implemented in
their respective classes rather than through an if tree in the CCompiler
class. This is cleaner abstraction and allows us to clean up the Fortran
compiler, which was calling CCompiler bound methods without an instance.
ICC doesn't use the same -fprofile-generate/-fprofile-use that GCC and
Clang use, instead it has -prof-gen and -prof-use. I've gone ahead and
added the threadsafe option to -prof-gen, as meson currently doesn't
have a way to specify that level of granularity and GCC and Clang's
profiles are threadsafe.
Because we need to inherit them in some cases, and python's
keyword-or-positional arguments make this really painful, especially
with inheritance. They do this in two ways:
1) If you want to intercept the arguments you need to check for both a
keyword and a positional argument, because you could get either. Then
you need to make sure that you only pass one of those down to the
next layer.
2) After you do that, if the layer below you decides to do the same
thing, but uses the other form (you used keyword by the lower level
uses positional or vice versa), then you'll get a TypeError since two
layers down got the argument as both a positional and a keyword.
All of this is bad. Fortunately python 3.x provides a mechanism to solve
this, keyword only arguments. These arguments cannot be based
positionally, the interpreter will give us an error in that case.
I have made a best effort to do this correctly, and I've verified it
with GCC, Clang, ICC, and MSVC, but there are other compilers like Arm
and Elbrus that I don't have access to.
Nirbheek Chauhan