`Driver::ClangExecutable` is derived from:
* (-canonical-prefixes default): `realpath` on the executable path
* (-no-canonical-prefixes) argv[0] (consult PATH if argv[0] is a word)
`Dir` and `ResourceDir` are derived from `ClangExecutable`. Both
variables are used to derive certain include and library paths.
`InstalledDir` is a related concept used to derive certain other paths.
`InstalledDir` is weird in the -canonical-prefixes mode: Clang
calls `make_absolute` but does not follow symlinks
(FIXME from 9ade6a9a747c49383ac747bd8ffaa6a0beaef71c).
This causes some search and library paths to be mix-and-matched.
The "Do a PATH lookup, if there are no directory components." logic
makes things worse.
`InstalledDir` is different when you invoke it via `PATH`:
```
% which clang
/usr/bin/clang
% clang -v |& grep InstalledDir
InstalledDir: /usr/bin
% /usr/lib/llvm-16/bin/clang -v |& grep InstalledDir
InstalledDir: /usr/lib/llvm-16/bin
```
I believe `InstalledDir` was a partial solution to
`-no-canonical-prefixes` and should be eventually removed.
This patch removes `SetInstallDir` and relies on Driver::Driver to set
`InstalledDir` to `Dir`. The behavior for regular file `clang` or
`-no-canonical-prefixes` is unchanged.
If a user creates a symlink to the regular file `clang` and uses the
default `-canonical-prefixes`, they now consistently get search and
library paths relative to the regular file `clang`, not mix-and-match
paths.
If a user creates a symlink to the regular file `clang` and replaces
some directorys from the actual installation, they should change the
symlink to a wrapper that calls the underlying clang with
`-no-canonical-prefixes`.
To match GCC (either crossing or not), which doesn't prepend target triple prefixes to `exec_prefixes`.
As an example, powerpc64le-linux-gnu-gcc does not search "powerpc64le-linux-gnu-${name}" in a -B path.
Summary:
Failure type 1:
This test can fail when the path of the build includes the strings
we're checking for. E.g "/gcc" is found in ".../gcc_7.3.0/..."
To correct this look for '"' on the end of all matches. So that we
only match the end of paths printed by clang -###.
(which would be ".../gcc_7.3.0/.../gcc" for the example)
Also look for other gcc names like gcc-x.y.z in the first check.
This confirms that the copy of clang we made is isolated as expected.
Failure type 2:
If you use a triple like "powerpc64le-linux-gnu" clang actually reports
"powerpc64le-unknown-linux-gnu". Then it searches for the
former.
That combined with Mac OS adding a version number to cmake's triple
means we can't trust cmake or clang to give us the one default triple.
To fix the test, write to both names. As they don't overlap with our
fake triple, we're still showing that the lookup works.
Reviewers: MaskRay, stevewan
Reviewed By: stevewan
Subscribers: miyuki, JDevlieghere, steven.zhang, stevewan, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D83055
This reverts commit f570d5810485fa6fb2e1009f795a899d79bd429f.
The test was failing on MacOS if you set
LLVM_DEFAULT_TARGET_TRIPLE. For example if you set it to
"x86_64-apple-darwin" clang actually uses
"x86_64-apple-darwin<version>".
To fix this get default triple from clang itself during the
test instead of substituting it in via lit.
Revert 028571d60843cb87e2637ef69ee09090d4526c62 to investigate
MacOS failure.
(also the review link was incorrect, should be
https://reviews.llvm.org/D79842)
Summary:
As seen in:
https://bugs.llvm.org/show_bug.cgi?id=45693
When clang looks for a tool it has a set of
possible names for it, in priority order.
Previously it would look for these names in
the program path. Then look for all the names
in the PATH.
This means that aarch64-none-elf-gcc on the PATH
would lose to gcc in the program path.
(which was /usr/bin in the bug's case)
This changes that logic to search each name in both
possible locations, then move to the next name.
Which is more what you would expect to happen when
using a non default triple.
(-B prefixes maybe should follow this logic too,
but are not changed in this patch)
Subscribers: kristof.beyls, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D79988
