* Reuse bytes of async function frames when non-async functions
make `noasync` calls. This prevents explosive stack growth.
* Zig now passes a stack size argument to the linker when linking ELF
binaries. Linux ignores this value, but it is available as a program
header called GNU_STACK. I prototyped some code that memory maps
extra space to the stack using this program header, but there was
still a problem when accessing stack memory very far down. Stack
probing is needed or not working or something. I also prototyped
using `@newStackCall` to call main and that does work around the
issue but it also brings its own issues. That code is commented out
for now in std/special/start.zig. I'm on a plane with no Internet,
but I plan to consult with the musl community for advice when I get a
chance.
* Added `noasync` to a bunch of function calls in std.debug. It's very
messy but it's a workaround that makes stack traces functional with
evented I/O enabled. Eventually these will be cleaned up as the root
bugs are found and fixed. Programs built in blocking mode are
unaffected.
* Lowered the default stack size of std.io.InStream (for the async
version) to 1 MiB instead of 4. Until we figure out how to get
choosing a stack size working (see 2nd bullet point above), 4 MiB
tends to cause segfaults due to stack size running out, or usage of
stack memory too far apart, or something like that.
* Default thread stack size is bumped from 8 MiB to 16 to match the
size we give for the main thread. It's planned to eventually remove
this hard coded value and have Zig able to determine this value
during semantic analysis, with call graph analysis and function
pointer annotations and extern function annotations.
* Add missing <stdint.h> include for uint8_t type declaration
* Add needed FreeBSD check to link to libpthread
* Apply patch to enable more tests in the FreeBSD CI
* fixed --verbose-cc printing an extra "zig" before the rest of
the command line
* windows-gnu targets use libfoo.a, foo.o extensions to match mingw
conventions.
The code assumed that the architecture-specific bits, found in the arch/
subfolder, were only overrides for the generic .c files.
Changed the logic to always include the whole architecture-specific
implementations and discard the generic ones, this way we won't exclude
files with no .c counterpart.
* 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.
