* build-exe does include the startup code that supplies _start for the
wasm32-freestanding target. Previously this did not occur because
of logic excluding "freestanding".
* build-lib for wasm32-freestanding target gets linked by LLD. To avoid
infinite recursion, compiler_rt and zig libc are built as objects
rather than libraries.
- no "lib" prefix and ".wasm" extension instead of ".a". Rather than
build-lib foo.zig producing "libfoo.a", now it produces "foo.wasm".
* go back to using `.o` extension for webassembly objects
* zig libc only provides _start symbol for wasm when linking libc.
to be installed when linking libc.
When zig links against libc, it requires a dynamic linker path.
Usually this can be determined based on the architecture and operating
system components of the target. However on some systems this is not
correct; because of this zig checks its own dynamic linker.
When zig is statically linked, this information is not available, and so
it resorts to using cc -print-filename=foo to find the dynamic linker
path.
Before this commit, Zig incorrectly exited with an error if there was
no c compiler installed. Now, Zig falls back to the dynamic linker
determined based on the arch and os when no C compiler can be found.
* rename std/special/builtin.zig to std/special/c.zig
not to be confused with @import("builtin") which is entirely
different, this is zig's multi-target libc implementation.
* WebAssembly: build-exe is for executables which have a main().
build-lib is for building libraries of functions to use from,
for example, a web browser environment.
- for now pass --export-all for libraries when there are any
C objects because we have no way to detect the list of exports
when compiling C code.
- stop passing --no-entry for executables. if you want --no-entry
then use build-lib.
* make the "musl" ABI the default ABI for wasm32-freestanding.
* zig provides libc for wasm32-freestanding-musl.
Stuffing all the files together and compiling the resulting blob with
the main program is a terrible idea.
Some files, namely the .S ones, must be run trough the C preprocessor
before assembling them (#2437).
Beside that the aggregate may be mis-compiled due to the presence of
some flags that affect the following code.
For example let's consider two files, a.s and b.s
a.s
```
fn1:
ret
.data
data1:
.word 0
```
b.s
```
fn2:
ret
```
Now, fn1 and fn2 will be both placed in the .text section as intended if
the two files are compiled separately. But if we merge them the `.data`
flag ends up placing fn2 in the wrong section!
This fixes a nasty crash where musl's memset ended up in the
non-executable data segment, leading to too many hours of
head-scratching.
Sadly due to a workaround for LLD linker limitations on macOS
we cannot put libuserland into an .a file; instead we have to use object
files. Again due to linker limitations, bundling compiler_rt.o into
another relocatable object also doesn't work. So we're left with
disabling stack probing on macOS for the stage1 self-hosted code.
These workarounds could all be removed if the macos support in the LLD
linker improved, or if Zig project had its own linker that did not have
these issues.
and use it when building libuserland.a
The self-hosted part of stage1 relies on zig's compiler-rt, and so we
include it in libuserland.a.
This should potentially be the default, but for now it's behind a linker
option.
self-hosted translate-c: small progress on translating functions.
`--static` is no longer an option. Instead, Zig makes things as static
as possible by default. `-dynamic` can be used to choose a dynamic
library rather than a static one.
`--enable-pic` is a new option. Usually it will be enabled
automatically, but in the case of build-exe with no dynamic libraries
on Linux or freestanding, Zig chooses off by default.
closes#1703closes#1828
* in Zig build scripts, getOutputPath() is no longer a valid function
to call, unless setOutputDir() was used, or within a custom make()
function. Instead there is more convenient API to use which takes
advantage of the caching system. Search this commit diff for
`exe.run()` for an example.
* Zig build by default enables caching. All build artifacts will go
into zig-cache. If you want to access build artifacts in a convenient
location, it is recommended to add an `install` step. Otherwise
you can use the `run()` API mentioned above to execute programs
directly from their location in the cache. Closes#330.
`addSystemCommand` is available for programs not built with Zig
build.
* Please note that Zig does no cache evicting yet. You may have to
manually delete zig-cache directories periodically to keep disk
usage down. It's planned for this to be a simple Least Recently
Used eviction system eventually.
* `--output`, `--output-lib`, and `--output-h` are removed. Instead,
use `--output-dir` which defaults to the current working directory.
Or take advantage of `--cache on`, which will print the main output
path to stdout, and the other artifacts will be in the same directory
with predictable file names. `--disable-gen-h` is available when
one wants to prevent .h file generation.
* `@cImport` is always independently cached now. Closes#2015.
It always writes the generated Zig code to disk which makes debug
info and compile errors better. No more "TODO: remember C source
location to display here"
* Fix .d file parsing. (Fixes the MacOS CI failure)
* Zig no longer creates "temporary files" other than inside a
zig-cache directory.
This breaks the CLI API that Godbolt uses. The suggested new invocation
can be found in this commit diff, in the changes to `test/cli.zig`.
Unlike the other glibc source code checked into the repo, `csu/init.c`
did not have a license clause that allowed linking without restrictions.
`_IO_stdin_used` is the only symbol in the file and appears to be a 20
year old compatibility shim for the glibc 2.0 ABI. Obsolete in 2.1.
