Packages that use libtool run it as a wrapper around the linker.
Before calling the linker, libtool will determine what libraries would
be linked, and check if there's a corresponding libtool
archive (libfoo.la) file in the same directory . This file
contains extra information about the library. This is especially
important for static linking, because static archives don't contain
dependency information, so we need libtool to use the .la files to
figure out which libraries actually need to be linked against.
But in Nixpkgs, this has never worked. libtool isn't able to find any
libraries, because only the compiler wrapper knows how to find them,
and the compiler wrapper is opaque to libtool. This is why
pkgsStatic.util-linuxMinimal doesn't build prior to this patch — it
depends on libpam, which depends on libaudit, and if libtool can't
find the .la file, nothing will tell the linker to also link against
libaudit when linking libpam. (It was previously possible to build a
static util-linux, because linux-pam only recently had the audit
dependency added.)
There are a couple of ways we could fix this, so that libtool knows
where to look for .la files.
* Set LD_LIBRARY_PATH/DYLD_LIBRARY_PATH/whatever, which libtool will
examine. This would have major side effects though, because the
dynamic linker looks at it too.
* Inject libtool scripts with the appropriate information. That's
what I've done here. It was the obvious choice because we're
already finding and modifying the libtool scripts, to remove paths
outside the Nix store that libtool might check in unsandboxed
builds. Instead of emptying out the system paths, we can
repopulate it with our own library paths.
(We can't use a wrapper like we do for other tools in Nixpkgs, because
libtool scripts are often distributed in source tarballs, so we can't
just add a wrapped version of libtool as a dependency. That's why
there's already the fixLibtool function in stdenv.)
With this change, libtool is able to discover .la files, and
pkgsStatic.util-linuxMinimal can build again, linking correctly
against libpam and libaudit.
This reverts commit 488395c0f8.
Currently, `nix print-dev-env` fails to execute if this function is present, because of its use of hex literals.
Until this issue (https://github.com/NixOS/nix/issues/5262) is solved, we should revert this to prevent breakage.
somehow `read -N 0` behavior changed in bash 5. `read -d ''` has identical behavior
the purpose of the function is to read stdin and exit 1 on a null byte (i.e. if stdin is the content of a binary)
(cherry picked from commit 5d0acf20f88b1820cb8b641cfc5a43e973122701)
When we "fix" libtool, we empty out its system library path to avoid
it discovering libraries in e.g. /usr when the sandbox is disabled.
But this also means that the checks libtool does to make sure it can
find the libraries its supposed to be linking to won't work. On Linux
and Darwin, this isn't a problem, because libtool doesn't actually
perform any checks, but it is on at least NetBSD and Cygwin[1].
So, we force libtool not to do these checks on any platform, bringing
the more exotic platforms into line with the existing behaviour on
Linux and Darwin.
Without this change, lots of library packages produce warnings like
this in their build output on the platforms with checks by default:
*** Warning: linker path does not have real file for library -lz.
*** I have the capability to make that library automatically link in when
*** you link to this library. But I can only do this if you have a
*** shared version of the library, which you do not appear to have
*** because I did check the linker path looking for a file starting
*** with libz but no candidates were found. (...for regex pattern test)
*** The inter-library dependencies that have been dropped here will be
*** automatically added whenever a program is linked with this library
*** or is declared to -dlopen it.
And dependent packages break because libtool doesn't link their
transitive dependencies. So making this change fixes _lots_ of
packages on those platforms.
[1]: https://git.savannah.gnu.org/cgit/libtool.git/tree/m4/libtool.m4?id=544fc0e2c2a03129a540aebef41ad32bfb5c06b8#n3445
Only bash 4+ works in setup.sh. To make sure this is obvious, we can
check BASH_VERSINFO to get the major version number of Bash.
While Bash 3 is pretty rare, it still comes stock in macOS.
We *could* provide a warning here for non-Bash shells, but it’s not
always clear whether they will work or not. Zsh should have no trouble
while busybox sh, fish, or any others. There’s no great way to detect
what feature set the shell supports.
Fixes#71625
By exporting it, we always make the new directories available
to subprocesses, regardless of whether the environment
variable existed before `nix-shell` was invoked.
This avoids the scenario where strictDeps is off and cross-compiled
XDG_DATA_DIRS content is brought into the environment.
While probably harmless for data like manpages and completion scripts,
this would cause issues when XDG_DATA_DIRS is used to find executables
or plugins. The Qt framework is known to behave like this and might
have run into incompatibilities.
XDG_DATA_DIRS is to /share as PATH is to /bin.
It was defined as part of the XDG basedir specification.
https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
While it originated from the X Desktop Group, it is not limited to
the X11 ecosystem, as evidenced by its use in bash-completion.
The removal of ` && -d "$pkg/bin"` is ok, because this optimization is
already performed by `addToSearchPath`.
Rewrite the `stripHash` helper function with 2 differences:
* Paths starting with `--` will no longer produce an error.
* Use Bash string manipulation instead of shelling out to `grep` and
`cut`. This should be faster.
A bunch of stdenv-internal variables were deleted in
1601a7fcce, but these are needed in the
fixup phase, whereas the rest are just needed for the initial work
(findInputs, etc) before the user phases.
CC @matthewbauer
Before, we very carefully unapplied and reapplied `set -u` so the rest
of Nixpkgs could continue to not fail on undefined variables. Let's rip
off the band-aid.
These can be used to determine whether a ELF file with ELF header is an
executable or shared library.
We can't implement it in pure bash, as bash has problems with null
bytes.
That's very much consistent with the spirit of nix-shell --pure
BTW, nix 1.x shells will be always treated as pure;
in that version detection isn't possible.
https://github.com/NixOS/nix/commit/1bffd83e1a9c
Some SSL libs don't react to $SSL_CERT_FILE.
That actually makes sense to me, as we add this behavior
as nixpkgs-specific, so it seems "safer" to use $NIX_*.
