MachO linker now handles `-needed-l<name>`, `-needed_library=<name>`
and `-needed_framework=<name>`. While on macOS `-l` is equivalent
to `-needed-l`, and `-framework` to `-needed_framework`, it can be
used to the same effect as on Linux if combined with `-dead_strip_dylibs`.
This commit also adds handling for `-needed_library` which is macOS
specific flag only (in addition to `-needed-l`).
Finally, in order to leverage new linker testing harness, this commit
added ability to specify lowering to those flags via `build.zig`:
`linkSystemLibraryNeeded` (and related), and `linkFrameworkNeeded`.
Includes both traditiona and incremental codepaths with one caveat that
in incremental case, the requested size cannot be smaller than the
default padding size due to prealloc required due to incremental nature
of linking.
Also parse `-headerpad_max_install_names`, however, not actionable just yet -
missing implementation.
Unlike targeting ELF-based OSes such as Linux, resolving system libs
on Darwin should follow one of two strategies: `-search_paths_first`
or `-search_dylibs_first` and hence we defer always forcing linking
a static library to the linker.
Ignore MachO-specific flag -search_paths_first, since it is the default
in zld and ld64.
Also see Jakub's comment[1]:
Changing topic slightly, @motiejus dunno if you noticed, with this
change building arm64 Zig binary fails on macos - it complains about
unknown -search_paths_first flag. This one is an easy fix: we should
ignore it since this is the default behaviour in both ld64 and zld.
[1]: https://github.com/ziglang/zig/pull/11906#issuecomment-1163545849
If page aligned requested pagezero size is 0, skip generating
__PAGEZERO segment.
Add misc improvements to the pipeline, and correctly transfer the
requested __PAGEZERO size to the linker.
Pass `-pagezero_size` to the MachO linker. This is the final
"unsupported linker arg" that I could chase that CGo uses. After this
and #11874 we may be able to fail on an "unsupported linker arg" instead
of emiting a warning.
Test case:
zig=/code/zig/build/zig
CGO_ENABLED=1 GOOS=darwin GOARCH=amd64 CC="$zig cc -target x86_64-macos" CXX="$zig c++ -target x86_64-macos" go build -a -ldflags "-s -w" cgo.go
I compiled a trivial CGo program and executed it on an amd64 Darwin
host.
To be honest, I am not entirely sure what this is doing. This feels
right after reading what this argument does in LLVM sources, but I am by
no means qualified to make MachO pull requests. Will take feedback.
This passes -Wl,-no-pie linker arg. Golang uses that. From the `ld(1)`
man page:
Create a position dependent executable. This is the default.
Not adding to the help text, because this is the default.
Note that the current documentation for the `-z noexecstack` is
incorrect. This indicates that an object *does not* require an
executable stack.
This is actually the default of LLD, and there has never been a way to
override this default by passing `-z execstack` to LLD.
This commit removes the redundant `-z noexecstack` option from
zig build-exe/build-lib/build-obj and ignores the option if passed
to zig cc for compatibility.
As far as I can tell, there is no reason for code to require an
executable stack. This option only exists because the stack was
originally executable by default and some programs came to depend
on that behavior. Instead, mprotect(2) may be used to make memory
pages executable.
Full RELRO is a hardening feature that makes it impossible to perform
certian attacks involving overwriting parts of the Global Offset Table
to invoke arbitrary code.
It requires all symbols to be resolved before execution of the program
starts which may have an impact on startup time. However most if
not all popular Linux distributions enable full RELRO by default for
all binaries and this does not seem to make a noticeable difference
in practice.
"Partial RELRO" is equivalent to `-z relro -z lazy`.
"Full RELRO" is equivalent to `-z relro -z now`.
LLD defaults to `-z relro -z lazy`, which means Zig's current `-z relro`
option has no effect on LLD's behavior.
The changes made by this commit are as follows:
- Document that `-z relro` is the default and add `-z norelro`.
- Pass `-z now` to LLD by default to enable full RELRO by default.
- Add `-z lazy` to disable passing `-z now`.
Warnings about non-implemented `-z nocopyreloc` are common when
compiling go code (including Go's tests themselves). Let's just
make it stop complaining.
Originally I thought interleaving AIR with MIR will be useful, however
as it stands, I have used it very sporadically, and recently, not at
all, and I do not think anyone else is actually using it. If there is
a simple error such as a wrong instruction emitted,
`objdump` is perfectly capable of narrowing it down, while if there's
something more subtle happening, regardless of having `--verbose-mir`
functionality or not, you still gotta go via the debugger which
offers a better view at interleaved source program with the emitted
machine code. Finally, I believe `-femit-asm` when we add it will offer a
more generic substitute.
stage2: change logic for detecting whether the main package is inside
the std package. Previously it relied on realpath() which is not portable.
This uses resolve() which is how imports already work.
* stage2: fix cleanup bug when creating Module
* flatten lib/std/special/* to lib/*
- this was motivated by making main_pkg_is_inside_std false for
compiler_rt & friends.
* rename "mini libc" to "universal libc"
Ideally on Windows, static libraries look like "foo.lib". However, CMake
and other build systems will unfortunately produce static libraries that
instead look like "libfoo.a". This patch makes Zig's CLI resolve "-lfoo"
arguments into static libraries that match this other pattern.
This patch fixes an issue with zig-bootstrap where it won't find the
LLVM, Clang, and LLD libraries.
Maybe after we have incremental compilation metadata serialization
and non-LLVM backends, it will make sense to switch this back. For now,
however, this makes successive `zig build` commands much faster.
Instead, just return ChildProcess directly. This structure does not
require a stable address, so we can put it on the stack just fine. If
someone wants it on the heap they should do.
const proc = try allocator.create(ChildProcess);
proc.* = ChildProcess.init(args, allocator);
Rather than allocating Decl objects with an Allocator, we instead allocate
them with a SegmentedList. This provides four advantages:
* Stable memory so that one thread can access a Decl object while another
thread allocates additional Decl objects from this list.
* It allows us to use u32 indexes to reference Decl objects rather than
pointers, saving memory in Type, Value, and dependency sets.
* Using integers to reference Decl objects rather than pointers makes
serialization trivial.
* It provides a unique integer to be used for anonymous symbol names,
avoiding multi-threaded contention on an atomic counter.
So that people can start experimenting with compiling their projects
with the self-hosted compiler.
I expect this commit to be reverted after #89 is closed.
This change adds a "--exclude" parameter to zig format, which can be
used to make sure that it does not process certain files or folders
when recursively walking a directory.
To do this, we simply piggy-back on the existing "seen" logic in zig
fmt and mark these files/folders as seen before processing begins.
This reverts commit 3701697a0a586e630a2452dea29951f0051a47fd.
The commit introduced a regression when building stage2 on nixOS where
the linker would fail to find relevant LLVM dynamic libraries as some
search dirs were missing.
With this change, we can now bake in entitlements into the binary.
Additionally, I see this as the first step towards full code signature
support which includes baking in Apple issued certificates for
redistribution, etc.
This brings back #10950, which was reverted in 5ab5e2e6731a9f1198df6c53134545ccc6a6bbd3
because it [introduced a regression in `zig run`](https://github.com/ziglang/zig/pull/10950#issuecomment-1049481212)
where the runtime arguments passed were incorrect.
I've fixed the issue, and notably this was the only location where we
directly relied on accessing arguments by index in this code still (all
other locations use the iterator proper) and so we should be all good to
go now.
Signed-off-by: Stephen Gutekanst <stephen@hexops.com>
Now we handle -o /dev/null equivalent to -fno-emit-bin because
otherwise our atomic rename into place will fail. This also
makes Zig do less work, avoiding pointless file system operations.
This reverts commit 136a43934bc08dc3aee85f1182904b97456601d3, reversing
changes made to 9dd839b7ed15d1191f3303d069cffe0473e03e83.
This broke the behavior of `zig run`.
Previously, Zig ignored -lgcc_s with a warning that this dependency is
redundant because it is satisfied by compiler-rt. However, sfackler
pointed out that it also provides exception handling functions. So if
Zig sees -lgcc_s on the linker line, it needs to fulfill this dependency
with libunwind.
I also made link_libc inferred to be on if libunwind is linked since
libunwind depends on libc.
