This lays the groundwork for #2879. This library will be built and linked when a
static libc is going to be linked into the compilation. Currently, that means
musl, wasi-libc, and MinGW-w64. As a demonstration, this commit removes the musl
C code for a few string functions and implements them in libzigc. This means
that those libzigc functions are now load-bearing for musl and wasi-libc.
Note that if a function has an implementation in compiler-rt already, libzigc
should not implement it. Instead, as we recently did for memcpy/memmove, we
should delete the libc copy and rely on the compiler-rt implementation.
I repurposed the existing "universal libc" code to do this. That code hadn't
seen development beyond basic string functions in years, and was only usable-ish
on freestanding. I think that if we want to seriously pursue the idea of Zig
providing a freestanding libc, we should do so only after defining clear goals
(and non-goals) for it. See also #22240 for a similar case.
LLD expects the library file name (minus extension) to be exactly libmingw32. By
calling it mingw32 previously, we prevented it from being detected as being in
LLD's list of libraries that are excluded from the MinGW-specific auto-export
mechanism.
b9d27ac252/lld/COFF/MinGW.cpp (L30-L56)
As a result, a DLL built for *-windows-gnu with Zig would export a bunch of
internal MinGW symbols. This sometimes worked out fine, but it could break at
link or run time when linking an EXE with a DLL, where both are targeting
*-windows-gnu and thus linking separate copies of mingw32.lib. In #23204, this
manifested as the linker getting confused about _gnu_exception_handler() because
it was incorrectly exported by the DLL while also being defined in the
mingw32.lib that was being linked into the EXE.
Closes#23204.
Windows is a ridiculous operating system designed by toddlers, and so
requires us to close all file handles in the `tmp/xxxxxxx` cache dir
before renaming it into `o/xxxxxxx`. We have a hack in place to handle
this for the main output file, but the MachO linker also outputs a file
with debug symbols, and we weren't closing it! This led to a fuckton of
CI failures when we enabled `.whole` cache mode by default for
self-hosted backends.
thanks jacob for figuring this out while i sat there
This can also be extended to ELF later as it means roughly the same thing there.
This addresses the main issue in #21721 but as I don't have a macOS machine to
do further testing on, I can't confirm whether zig cc is able to pass the entire
cgo test suite after this commit. It can, however, cross-compile a basic program
that uses cgo to x86_64-macos-none which previously failed due to lack of -x
support. Unlike previously, the resulting symbol table does not contain local
symbols (such as C static functions).
I believe this satisfies the related donor bounty: https://ziglang.org/news/second-donor-bounty
Functions like isMinGW() and isGnuLibC() have a good reason to exist: They look
at multiple components of the target. But functions like isWasm(), isDarwin(),
isGnu(), etc only exist to save 4-8 characters. I don't think this is a good
enough reason to keep them, especially given that:
* It's not immediately obvious to a reader whether target.isDarwin() means the
same thing as target.os.tag.isDarwin() precisely because isMinGW() and similar
functions *do* look at multiple components.
* It's not clear where we would draw the line. The logical conclusion before
this commit would be to also wrap Arch.isX86(), Os.Tag.isSolarish(),
Abi.isOpenHarmony(), etc... this obviously quickly gets out of hand.
* It's nice to just have a single correct way of doing something.
* arm_apcs is the long dead "OABI" which we never had working support for.
* arm_aapcs16_vfp is for arm-watchos-none which is a dead target that we've
dropped support for.
This ensure capacity call does not match the number of
appendAssumeCapacity() calls that follow it. Fix this.
This was discovered due to hitting the assertion failure in
appendAssumeCapacity() while building river.
I'm not sure how to isolate a minimal reproducer for a test.
Instead, `source`, `tree`, and `zir` should all be optional. This is
precisely what we're actually trying to model here; and `File` isn't
optimized for memory consumption or serializability anyway, so it's fine
to use a couple of extra bytes on actual optionals here.
If this isn't done, LTO can completely miscompile the input bitcode modules for
certain targets where we need to explicitly set these ABIs (because LLVM's
defaults are bad).
This is more verbose, but at least we now get a compile error instead of UB when
a new feature is added to std.Target.wasm.Feature but not to link.Wasm.Feature.
This will mainly be used when targeting our wasm2c implementation which has no
problem with zero-length bulk memory operations, as a non-standard extension.
This was done by regex substitution with `sed`. I then manually went
over the entire diff and fixed any incorrect changes.
This diff also changes a lot of `callconv(.C)` to `callconv(.c)`, since
my regex happened to also trigger here. I opted to leave these changes
in, since they *are* a correct migration, even if they're not the one I
was trying to do!
this logic has not yet been ported to the new design, but the logic is
safe and sound in the git history and does not need to also live as
commented out code
