The compilers module is rather large and confusing, with spaghetti
dependencies going every which way. I'm planning to start breaking out
the internal representations into a mixins submodule, for things that
shouldn't be required outside of the compilers module itself.
We were setting the base options for the Objective-C compiler
manually, due to which options such as b_bitcode and b_ndebug were not
getting set at all.
The base options here are the same as for C code with the Clang
compiler, so just use the same inherited list.
Also expand the bitcode test to ObjC and ObjC++ so this doesn't happen
again.
In most cases instead pass `for_machine`, the name of the relevant
machines (what compilers target, what targets run on, etc). This allows
us to use the cross code path in the native case, deduplicating the
code.
As one can see, environment got bigger as more information is kept
structured there, while ninjabackend got a smaller. Overall a few amount
of lines were added, but the hope is what's added is a lot simpler than
what's removed.
Currently C++ inherits C, which can lead to diamond problems. By pulling
the code out into a standalone mixin class that the C, C++, ObjC, and
Objc++ compilers can inherit and override as necessary we remove one
source of diamonding. I've chosen to split this out into it's own file
as the CLikeCompiler class is over 1000 lines by itself. This also
breaks the VisualStudio derived classes inheriting from each other, to
avoid the same C -> CPP inheritance problems. This is all one giant
patch because there just isn't a clean way to separate this.
I've done the same for Fortran since it effectively inherits the
CCompiler (I say effectively because was it actually did was gross
beyond explanation), it's probably not correct, but it seems to work for
now. There really is a lot of layering violation going on in the
Compilers, and a really good scrubbing would do this code a lot of good.
Previously cross, but not native, external args were used. Then in
d451a4bd97 the cross special cases were
removed, so external args are never used.
This commit switches that so they are always used. Sanity checking works
just the same as compiler checks like has header / has library.
* Enums are strongly typed and make the whole
`gcc_type`/`clang_type`/`icc_type` distinction
redundant.
* Enums also allow extending via member functions,
which makes the code more generalisable.
Dylan Baker