This patch allows users to configure clang with option
e.g. `-DCLANG_CONFIG_FILE_USER_DIR=~/.config/clang` or invoke clang
with `--config-user-dir=~/.config/clang`.
Patch merged on behalf of @paperchalice (LJC)
Differential Revision: https://reviews.llvm.org/D136940
Add support for a CLANG_NO_DEFAULT_CONFIG envvar that works like
the --no-default-config option when set to a non-empty value. Use it
to disable loading system configuration files during the test suite
runs.
Configuration files can change the driver behavior in extensive ways,
and it is neither really possible nor feasible to account for or undo
the effects of even the most common configuration uses. Therefore,
the most reasonable option seems to be to ignore configuration files
while running the majority of tests (with the notable exception of tests
for configuration file support).
Due to the diversity of ways that %clang is used in the test suite,
including using it to copy or symlink the clang executable, as well to
call -cc1 and -cc1as modes, it is not feasible to pass the explicit
options to disable config loading either. Using an environment variable
has the advantage of being easily applied across the test suite
and easily unset for default configuration file loading tests.
Differential Revision: https://reviews.llvm.org/D134905
Change the default config file loading logic to be more flexible
and more readable at the same time. The new algorithm focuses on four
locations, in order:
1. <triple>-<mode>.cfg using real driver mode
2. <triple>-<mode>.cfg using executable suffix
3. <triple>.cfg + <mode>.cfg using real driver mode
4. <triple>.cfg + <mode>.cfg using executable suffix
This is meant to preserve reasonable level of compatibility with
the existing use, while introducing more flexibility and making the code
simpler. Notably:
1. In this layout, the actual target triple is normally respected,
and e.g. in `-m32` build the `x86_64-*` configs will never be used.
2. Both real driver mode (preferable) and executable suffix are
supported. This permits correctly handling calls with explicit
`--driver-mode=` while at the same time preserving compatibility
with the existing code.
3. The first two locations provide users with the ability to override
configuration per specific target+mode combinaton, while the next two
make it possible to independently specify per-target and per-mode
configuration.
4. All config file locations are applicable independently of whether
clang is started via a prefixed executable, or bare `clang`.
5. If the target is not explicitly specified and the executable prefix
does not name a valid triple, it is used instead of the actual target
triple for backwards compatibility.
This is particularly meant to address Gentoo's use case for
configuration files: to configure the default runtimes (i.e. `-rtlib=`,
`-stdlib=`) and `--gcc-install-dir=` for all the relevant drivers,
as well as to make it more convenient for users to override `-W` flags
to test compatibility with future versions of Clang easier.
Differential Revision: https://reviews.llvm.org/D134337
Support specifying multiple configuration files via multiple `--config`
options. When multiple files are specified, the options from subsequent
files are appended to the options from the initial file.
While at it, remove the incorrect assertion about CfgFileName being
non-empty. It can be empty if `--config ""` is passed, and it makes
sense to report it as non-existing file rather than crash.
Differential Revision: https://reviews.llvm.org/D134270
Disable transformations (e.g. attempting to replace target architecture)
in the config filename that is passed explicitly via `--config`. This
behavior is surprising and confusing -- if user passes an explicit
config filename, Clang should use it as is. The transformations are
still applied when the name is deduced from filename.
Update the tests accordingly. This primarily ensures that full filename
with .cfg suffix is passed to --config (appending `.cfg` implicitly is
not documented, and would collide with use of filenames with other
suffixes). The config-file2.c suite is removed entirely as it tested
the transformations on the argument to --config. However, the aspects
of that that were not tested as part of config-file3.c are now added
there (based on config filename deduced from executable).
This change streamlines the code in Driver::loadConfigFile(), opening
the possibility of further changes, including support for handling
multiple --config options and refactoring of filename deduction.
Differential Revision: https://reviews.llvm.org/D134208
Instead of checking if each symlink exists before removing it,
remove the whole temp dir housing the symlinks before recreating it.
This is a bit shorter, conceptually simpler (in that the first
and consecutive test runs have more similar behavior), it's what we're
already doing in almost all places where we do it, and it works if the
symlink exists but is a dead link (e.g. when it points into the build
dir but the build dir is renamed).
No intended behavior change.
If -no-canonical-prefixes isn't used, the clang executable name used
is the one of the actual executable, not the name of the symlink that
the user invoked.
In these cases, the target prefix was overridden based on the clang
executable name. (On the other hand the implicit -target option
that such a symlink adds, is added as an actual command line parameter
in tools/driver/driver.cop, before resolving the symlink and finding
the actual clang executable.
Use the original ClangNameParts (set from argv[0] in
tools/driver/driver.cpp) if it seems to be initialized propery.
All existing tests of this feature used -no-canonical-prefixes
(possibly because it also makes the driver look in the directory
of the symlink instead of the directory of the executable); add
another one that uses --config-user-dir= to specify the directory
instead. (For actual users of such symlinks, outisde of the test
suite, the directory is probably the same for both.)
This makes this feature work more like what the documentation
describes.
Differential Revision: https://reviews.llvm.org/D45964
llvm-svn: 330871
Clang is inherently a cross compiler and can generate code for any target
enabled during build. It however requires to specify many parameters in the
invocation, which could be hardcoded during configuration process in the
case of single-target compiler. The purpose of configuration files is to
make specifying clang arguments easier.
A configuration file is a collection of driver options, which are inserted
into command line before other options specified in the clang invocation.
It groups related options together and allows specifying them in simpler,
more flexible and less error prone way than just listing the options
somewhere in build scripts. Configuration file may be thought as a "macro"
that names an option set and is expanded when the driver is called.
Use of configuration files is described in `UserManual.rst`.
Differential Revision: https://reviews.llvm.org/D24933
llvm-svn: 321621
Clang is inherently a cross compiler and can generate code for any target
enabled during build. It however requires to specify many parameters in the
invocation, which could be hardcoded during configuration process in the
case of single-target compiler. The purpose of configuration files is to
make specifying clang arguments easier.
A configuration file is a collection of driver options, which are inserted
into command line before other options specified in the clang invocation.
It groups related options together and allows specifying them in simpler,
more flexible and less error prone way than just listing the options
somewhere in build scripts. Configuration file may be thought as a "macro"
that names an option set and is expanded when the driver is called.
Use of configuration files is described in `UserManual.rst`.
Differential Revision: https://reviews.llvm.org/D24933
llvm-svn: 321587
Michał Górny