The VFS overlay mapping between virtual paths and real paths is done through
the 'external-contents' entries in YAML files, which contains hardcoded paths
to the real files.
When a module compilation crashes, headers are dumped into <name>.cache/vfs
directory and are mapped via the <name>.cache/vfs/vfs.yaml. The script
generated for reproduction uses -ivfsoverlay pointing to file to gather the
mapping between virtual paths and files inside <name>.cache/vfs. Currently, we
are only capable of reproducing such crashes in the same machine as they
happen, because of the hardcoded paths in 'external-contents'.
To be able to reproduce a crash in another machine, this patch introduces a new
option in the VFS yaml file called 'overlay-relative'. When it's equal to
'true' it means that the provided path to the YAML file through the
-ivfsoverlay option should also be used to prefix the final path for every
'external-contents'.
Example, given the invocation snippet "... -ivfsoverlay
<name>.cache/vfs/vfs.yaml" and the following entry in the yaml file:
"overlay-relative": "true",
"roots": [
...
"type": "directory",
"name": "/usr/include",
"contents": [
{
"type": "file",
"name": "stdio.h",
"external-contents": "/usr/include/stdio.h"
},
...
Here, a file manager request for virtual "/usr/include/stdio.h", that will map
into real path "/<absolute_path_to>/<name>.cache/vfs/usr/include/stdio.h.
This is a useful feature for debugging module crashes in machines other than
the one where the error happened.
Differential Revision: http://reviews.llvm.org/D17457
rdar://problem/24499339
llvm-svn: 261552
Handle ".", ".." and "./" with trailing slashes while collecting files
to be dumped into the vfs overlay directory.
Include the support for symlinks into components. Given the path:
/install-dir/bin/../lib/clang/3.8.0/include/altivec.h, if "bin"
component is a symlink, it's not safe to use `path::remove_dots` here,
and `realpath` is used to get the right answer. Since `realpath`
is expensive, we only do it at collecting time (which only happens
during the crash reproducer) and cache the base directory for fast lookups.
Overall, this makes the input to the VFS YAML file to be canonicalized
to never contain traversal components.
Differential Revision: http://reviews.llvm.org/D17104
rdar://problem/24499339
llvm-svn: 261551
FixedCompilationDatabase sets the working dir to "." by default. For
chdir(".") this is a noop but this lead to InMemoryFileSystem to create
bogus paths. Fixes PR25327.
llvm-svn: 257260
Make RedirectedFileSystem::openFilForRead(path)->status() the same as
RedirectedFileSystem::status(path). Previously we would just get the
status of the underlying real file, which would not have the IsVFSMapped
bit set.
This fixes rebuilding a module that has an include that is relative to
the includer where we will lookup the real path of that file before we
lookup the VFS location.
rdar://problem/23640339
llvm-svn: 255312
Summary: It breaks the build for the ASTMatchers
Subscribers: klimek, cfe-commits
Differential Revision: http://reviews.llvm.org/D13893
llvm-svn: 250827
This is a more principled version of what I did earlier. Path
normalization is generally a good thing, but may break users in strange
environments, e. g. using lots of symlinks. Let the user choose and
default it to on.
This also changes adding a duplicated file into returning an error if
the file contents are different instead of an assertion failure.
Differential Revision: http://reviews.llvm.org/D13658
llvm-svn: 250060
Actually the only special path we have to handle is ./foo, the rest is
tricky to get right so do the same thing as the existing YAML vfs here.
llvm-svn: 250036
This can fail badly if we're overlaying a real file system and there are
symlinks there. Just keep the path as-is for now.
This essentially reverts r249830.
llvm-svn: 250021
- Rename it to RedirectingFileSystem. This is what it does, YAML is just a
serialization format for it.
- Consistently use unique_ptr for memory management.
No functional change intended.
llvm-svn: 249532
Apart from being cleaner this also means that clang-format no longer has
access to the host file system. This isn't necessary because clang-format
never reads includes :)
Includes minor tweaks and bugfixes found in the VFS implementation while
running clang-format tests.
llvm-svn: 249385
For RealFileSystem this is getcwd()/chdir(), the synthetic file systems can
make up one for themselves. OverlayFileSystem now synchronizes the working
directories when a new FS is added to the overlay or the overlay working
directory is set. This allows purely artificial file systems that have zero
ties to the underlying disks.
Differential Revision: http://reviews.llvm.org/D13430
llvm-svn: 249316
This is a simple file system tree of memory buffers that can be filled by a
client. In conjunction with an OverlayFS it can be used to make virtual
files accessible right next to physical files. This can be used as a
replacement for the virtual file handling in FileManager and which I intend
to remove eventually.
llvm-svn: 249315
The patch is generated using this command:
$ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
work/llvm/tools/clang
To reduce churn, not touching namespaces spanning less than 10 lines.
llvm-svn: 240270
Now that SmallString is a first-class citizen, most SmallString::str()
calls are not required. This patch removes a whole bunch of them, yet
there are lots more.
There are two use cases where str() is really needed:
1) To use one of StringRef member functions which is not available in
SmallString.
2) To convert to std::string, as StringRef implicitly converts while
SmallString do not. We may wish to change this, but it may introduce
ambiguity.
llvm-svn: 232622
Sorry for the noise, I managed to miss a bunch of recent regressions of
include orderings here. This should actually sort all the includes for
Clang. Again, no functionality changed, this is just a mechanical
cleanup that I try to run periodically to keep the #include lines as
regular as possible across the project.
llvm-svn: 225979
For now, this is only used by its unit tests. It is similar to the API
in llvm::sys::fs::recursive_directory_iterator, but without some of the
more complex features like requesting that the iterator not recurse into
the next directory, for example.
llvm-svn: 211732
The API is based on sys::fs::directory_iterator, but it allows iterating
over overlays and the yaml-based VFS. For now, it isn't used by
anything (except its tests).
llvm-svn: 211623
If we lookup a path using its 'real' path first, we need to ensure that
when we run header search we still use the VFS-mapped path or we will
not be able to find the corresponding module for the header.
The real problem is that we tie the name of a file to its underlying
FileEntry, which is uniqued by inode, so we only ever get the first name
it is looked up by. This doesn't work with modules, which rely on a
specific file system structure. I'm hoping to have time to write up a
proposal for fixing this more permanently soon, but as a stopgap this
patch updates the name of the file's directory if it comes from a VFS
mapping.
llvm-svn: 209534
Bruno Cardoso Lopes