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
This adds clarification to the getGlobalSymbol doc comments,
as well as renames the `addExternFn` function for MachO to `getGlobalSymbol`.
This function will now be called from 'src/link.zig' as well.
Finally, this also enables compiling zig's libc using LLVM even though
the `fno-LLVM` flag is given.
`genFunctype` now accepts calling convention, param types, and return type
as part of its function signature rather than `fnData`. This means
we no longer have to create a dummy for our intrinsic call abstraction.
This also adds support for f16 division and builtins such as `@ceil` & more.
Rather than checking if the user wants to use LLVM for the current compilation,
check for the existance of LLVM as part of the compiler. This is temporarily,
until other backends gain the ability to compiler LLVM themselves.
This means that when a user passed `-fno-LLVM` we will use the native
backend for the user's code, but use LLVM for compiler-rt.
This also fixes emitting names for symbols in the Wasm linker,
by deduplicating symbol names when multiple symbols point the same object.
Implements `@mulAdd` for floats with bitsize 16, where it generates
a call into compiler-rt's `fmaf` function. Note that arguments
for fmaf are different in order than `@mulAdd`.
This implements binary operations and comparisons
for floats with bitsize 16. It does this by calling into
compiler-rt to first extend the float to 32 bits, perform the operation,
and then finally truncate back to 16 bits. When loading and storing the f16,
we do this as an unsigned 16bit integer.
Rather than finding the original object file, we seekTo to the
object file's position within the archive file, and from there open
a new file handle. This file handle is passed to the `Object` parser
which will create the object.
When a new symbol is resolved to an existing symbol where
it doesn't overwrite the existing symbol, we now add this symbol
to the discarded list. This is required so when any relocation points
to the symbol, we can retrieve the correct symbol it's resolved by instead.
When performing relocations for a type index,
we first check if the target symbol is undefined. In which case,
we will obtain the type from the `import` rather than look into the
`functions` table.
This implements a very basic archive file parser that validates
the magic bytes, and then parses the symbol table and stores
the symbol and their position.
Multiple symbols can point to the same function, this means that when we loop over
the symbol list, we must deduplicate those functions being added twice.
Additionaly, we must also ensure that when we append a new type and set the type
index on a function, we must not do this again for the same function.
This commit also implements sorting of code atoms to ensure their order matches
the order of the function section to ensure the function signature matches
that of the function body.
Implements the creation of an undefined symbol for a compiler-rt intrinsic.
Also implements the building of the function call to said compiler-rt intrinsic.
The for-loop in dump() would index out of bounds if `t.index` is greater
than size, because `end` is the maximum of `t.index` and `size` rather than the
minimum.
This approach is more inline with what LLVM/LLD does for testing
of their output, and seems to be more generic and easier to extend
than implementing a lot of repetitive and nontrivial comparison
logic when working directly on structures.
CheckMachOStep specialises CheckFileStep into directed (surgical)
MachO file fuzzy searches. This will be the building block for
comprehensive MachO linker tests.
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.
