Since commit 1c2d031cbd (Add -E cmake_llvm_rc to preprocess files for
llvm-rc, 2020-01-14, v3.17.0-rc1~24^2) we pass the full target `<FLAGS>`
to the llvm-rc resource compiler, but we should pass only `<DEFINES>`.
Fixes: #20414
Add an additional include flag to PCH usage command line to fix programs
that rely on `compile_commands.json` file. Pass it to the preprocessor
directly to avoid compiler driver to change it to '-include-pch'.
When preprocessor is requested to preprocess a file, it tries to get
the original filename from '.pch' and uses that file for preprocessing.
CMake generates a '.pch' file from the '.hxx' file by passing an empty
'.cxx' source file to the compiler as a compilation unit and the header
file with the '-include' flag. After that, compiler puts compilation
unit filename in the '.pch' as the original filename.
However, CMake build system uses empty file as the source file and
passes the header file using '-include-pch' flag. As a result, Clang
uses the wrong file for preprocessing and produces the corrupted
preprocessed file.
Fixes: #20355
Signed-off-by: Sergey Larin <cerg2010cerg2010@mail.ru>
llvm-rc requires preprocessed rc files. The CMake command line tool
cmake_llvm_rc enables channing the preprocessor call and the resource
compiler and make this appear as single compilation step.
When llvm-rc is detected as resource compiler, the RC compilation step
is set to use this command.
This allows building .s/.S assembly code, and makes sure that the
`-fPIC` option isn't passed to the compiler (as it errors out on
Clang and causes a loud warning on GCC).
Modern distributions of packages built with MinGW tools provide `.dll.a`
import libraries. Prefer those instead of finding plain `.dll` files.
This avoids accidentally finding unrelated Windows `.dll` files.
Fixes: #20019
dca9c33abc Tests: Remove old IPO test
c856d4556b bindexplib: supporting llvm bitcode formats using llvm-nm
079b8e2916 Clang: prefer lld-link over link.exe
6e3655db2c Clang: add LTO support for GNU-command line clang on windows
Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !3527
This change modifies how CMAKE_RC_COMPILER is configured to improve
the out-of-box experience for developers using Clang on Windows.
The previous behavior was to require the user to explicitly specify
the resource compiler when CMake was called. The new behavior
is to automatically attempt to locate the MSVC rc binary and use that
if it's found. If rc is not available, CMake will now fall back to
Clang's llvm-rc binary.
With this change in place, trivial C/C++ programs can be generated
with Ninja and Clang on Windows without running into errors about
a missing resource compiler.
Fixes: #19318
Per-source copyright/license notice headers that spell out copyright holder
names and years are hard to maintain and often out-of-date or plain wrong.
Precise contributor information is already maintained automatically by the
version control tool. Ultimately it is the receiver of a file who is
responsible for determining its licensing status, and per-source notices are
merely a convenience. Therefore it is simpler and more accurate for
each source to have a generic notice of the license name and references to
more detailed information on copyright holders and full license terms.
Our `Copyright.txt` file now contains a list of Contributors whose names
appeared source-level copyright notices. It also references version control
history for more precise information. Therefore we no longer need to spell
out the list of Contributors in each source file notice.
Replace CMake per-source copyright/license notice headers with a short
description of the license and links to `Copyright.txt` and online information
available from "https://cmake.org/licensing". The online URL also handles
cases of modules being copied out of our source into other projects, so we
can drop our notices about replacing links with full license text.
Run the `Utilities/Scripts/filter-notices.bash` script to perform the majority
of the replacements mechanically. Manually fix up shebang lines and trailing
newlines in a few files. Manually update the notices in a few files that the
script does not handle.
Teach the compiler identification preprocessor tests to report when
Clang simulates MSVC, and what version. If not MSVC, assume GNU.
Teach compiler information modules Clang-(C|CXX) to recognize when Clang
simulates MSVC and skip loading the GNU information.
Teach the Windows-MSVC platform information to recognize when it is
loaded as the simulated compiler and use that version information
instead of the real compiler's (different) version scheme.
Add platform modules Windows-Clang-(C|CXX) and support module
Windows-Clang to load either Windows-MSVC or Windows-GNU and wrap
the corresponding information macros.
