When cross-compiling to Windows using lld, we want the driver to invoke
it as lld-link rather than lld-link.exe. On Windows, the LLVM fs
functions take care of adding the .exe suffix where necessary, so we can
just drop the addition in the toolchain entirely.
Differential Revision: https://reviews.llvm.org/D33923
llvm-svn: 304761
clang-cl works best when the user runs vcvarsall to set up
an environment before running, but even this is not enough
on VC 2017 when cross compiling (e.g. using an x64 toolchain
to target x86, or vice versa).
The reason is that although clang-cl itself will have a
valid environment, it will shell out to other tools (such
as link.exe) which may not. Generally we solve this through
adding the appropriate linker flags, but this is not enough
in VC 2017.
The cross-linker and the regular linker both link against
some common DLLs, but these DLLs live in the binary directory
of the native linker. When setting up a cross-compilation
environment through vcvarsall, it will add *both* directories
to %PATH%, so that when cl shells out to any of the associated
tools, those tools will be able to find all of the dependencies
that it links against. If you don't do this, link.exe will
fail to run because the loader won't be able to find all of
the required DLLs that it links against.
To solve this we teach the driver how to spawn a process with
an explicitly specified environment. Then we modify the
PATH before shelling out to subtools and run with the modified
PATH.
Patch by Hamza Sood
Differential Revision: https://reviews.llvm.org/D30991
llvm-svn: 298098
2017 changes the way you find an installed copy of
Visual Studio as well as its internal directory layout.
As a result, clang-cl was unable to find VS2017 even
when you had run vcvarsall to set up a toolchain
environment. This patch updates everything for 2017
and cleans up the way we handle a tiered search a la
environment -> installation -> PATH for which copy
of Visual Studio to bind to.
Patch originally by Hamza Sood, with some fixups for landing.
Differential Revision: https://reviews.llvm.org/D30758
llvm-svn: 297851
Summary:
(This is a move-only refactoring patch. There are no functionality changes.)
This patch splits apart the Clang driver's tool and toolchain implementation
files. Each target platform toolchain is moved to its own file, along with the
closest-related tools. Each target platform toolchain has separate headers and
implementation files, so the hierarchy of classes is unchanged.
There are some remaining shared free functions, mostly from Tools.cpp. Several
of these move to their own architecture-specific files, similar to r296056. Some
of them are only used by a single target platform; since the tools and
toolchains are now together, some helpers now live in a platform-specific file.
The balance are helpers related to manipulating argument lists, so they are now
in a new file pair, CommonArgs.h and .cpp.
I've tried to cluster the code logically, which is fairly straightforward for
most of the target platforms and shared architectures. I think I've made
reasonable choices for these, as well as the various shared helpers; but of
course, I'm happy to hear feedback in the review.
There are some particular things I don't like about this patch, but haven't been
able to find a better overall solution. The first is the proliferation of files:
there are several files that are tiny because the toolchain is not very
different from its base (usually the Gnu tools/toolchain). I think this is
mostly a reflection of the true complexity, though, so it may not be "fixable"
in any reasonable sense. The second thing I don't like are the includes like
"../Something.h". I've avoided this largely by clustering into the current file
structure. However, a few of these includes remain, and in those cases it
doesn't make sense to me to sink an existing file any deeper.
Reviewers: rsmith, mehdi_amini, compnerd, rnk, javed.absar
Subscribers: emaste, jfb, danalbert, srhines, dschuff, jyknight, nemanjai, nhaehnle, mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D30372
llvm-svn: 297250
Shoaib Meenai