This reinstates the libSystem selective symbol export machinery we used
to have, but locks it to the symbols that were present in 10.11 and skips
the actual compiled code we put into that library in favor of the system
initialization code. That should make it more stable and less likely to
do weird stuff than the last time we did this.
The 3.8 upgrade was premature and appears to be breaking a load of stuff
that I can't look into right now. Will take it back to 3.8 and test more
thoroughly before pushing more broadly. I should learn to change fewer
variables at a time :)
It's a long build and generally painful to split into smaller commits,
so I apologize for lumping many changes into one commit but this is far
easier.
There are still several outdated parts of the darwin stdenv but these
changes should bring us closer to the goal.
Fixes#18461
Commit 2040a9ac574fffd36fe20130897ccec2d5928827 changed the order of
$PATH elements, causing initialpath to appear after buildInputs. Thus
gnugrep ended up depending on bin/sh from bootstrapTools, rather than
from pkgs.bash. The fix is to provide pkgs.bash via buildInputs rather
than initialPath.
http://hydra.nixos.org/build/33276697
The $lib output refers to the terminfo database in $out, which is about
10x larger than the ncurses shared library. Splitting these outputs
saves a small amount of space for any derivations that use the terminfo
database but not the ncurses library, but we do not have evidence that
any such exist.
The ld-wrapper.sh script calls `readlink` in some circumstances. We need
to ensure that this is the `readlink` from the `coreutils` package so
that flag support is as expected.
This is accomplished by explicitly setting PATH at the top of each shell
script.
Without doing this, the following happens with a trivial `main.c`:
```
nix-env -f "<nixpkgs>" -iA pkgs.clang
$ clang main.c -L /nix/../nix/store/2ankvagznq062x1gifpxwkk7fp3xwy63-xnu-2422.115.4/Library -o a.out
readlink: illegal option -- f
usage: readlink [-n] [file ...]
```
The key element is the `..` in the path supplied to the linker via a
`-L` flag. With this patch, the above invocation works correctly on
darwin, whose native `/usr/bin/readlink` does not support the `-f` flag.
The explicit path also ensures that the `grep` called by `cc-wrapper.sh`
is the one from Nix.
Fixes#6447
This un-hardcodes the bootstrap tools passed into the Darwin stdenv and
thus allows us to quickly iterate on improving the design of the full
bootstrap process. We can easily change the contents of the bootstrap
tools and evaluate an entire bootstrap all the way up to real packages.
92188d9d1751892ddbf8913da73dfc150d18fadb broke the case where the user
has Xcode but not the command-line tools. So this commit restores
using xcrun to get the path to the SDK (falling back to / for the
non-Xcode case).
http://hydra.nixos.org/build/19953295
This makes stuff build with Xcode 6.1 on Mac OS X 10.9 (where we got
errors like "ld: file not found:
/usr/lib/system/libsystem_coreservices.dylib for architecture x86_64" due to the use of the 10.10 SDK).
In 3.3, a C++ class defined in a header will get a typeinfo symbol
like this (e.g. in Nix's src/libutil/util.o):
(__DATA,__datacoal_nt) weak external typeinfo for nix::BaseError
But in 3.4, this has changed to:
(__DATA,__datacoal_nt) weak external automatically hidden typeinfo for nix::BaseError
This causes the linker to change the symbol to:
(__DATA,__data) non-external (was signed char private external) typeinfo for nix::BaseError
i.e. losing its weak linkage. But without weak linkage, dynamic_cast
and other RTTI-based mechanisms (such as catching an exception of a
certain type) don't work across shared libraries / executables.
The clang compiler in the SDK doesn't have this behaviour, but it's
not clear exactly which version it is (it just says "based on LLVM
3.4svn").
Copying /usr/lib/system/libunwind.dylib at evaluation time doesn't
work (e.g. on Hydra). And copying binary system libraries is a bad
idea anyway for license reasons.
