This is a stupid Clang-ism:
❯ cat test.c
int main() {
int value = 42;
int const *value_ptr = &value;
int location;
__atomic_store(&location, value_ptr, __ATOMIC_SEQ_CST);
}
❯ gcc test.c -fsyntax-only
❯ clang test.c -fsyntax-only
test.c:5:31: warning: passing 'const int *' to parameter of type 'int *' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
5 | __atomic_store(&location, value_ptr, __ATOMIC_SEQ_CST);
| ^~~~~~~~~
1 warning generated.
I have no idea why Clang doesn't define these builtins as taking const pointers
for the parameters that are only read from. Anyway, after the next zig1.wasm
update, this change should shut up these warnings that we've been seeing in CI
during bootstrap for ages.
If present, these headers are usable even when compiling for older C language
versions.
Most notably, this enables zig.h atomics to work with slimcc and TinyCC in C99
mode (and earlier).
* Make it work for thumb and aarch64.
* Clean up std.os.windows.teb() a bit.
I also updated stage1/zig.h since the changes are backwards-compatible and are
necessary due to the std.os.windows changes that call the newly-added functions.
This was causing zig2.exe to crash during bootstrap, because there was an atomic
load of read-only memory, and the attempt to write to it as part of the (idempotent)
atomic exchange was invalid.
Aligned reads (of u32 / u64) are atomic on x86 / x64, so this is replaced with an
optimization-proof load (`__iso_volatile_load8*`) and a reordering barrier.
This reverts commit a7de02e052.
This did not implement the accepted proposal, and I did not sign off
on the changes. I would like a chance to review this, please.
This reverts commit 7161ed79c4, reversing
changes made to 3f2a65594e.
Unfortunately, this sat in the PR queue too long and the merge broke the
zig1.wasm bootstrap process.
Changes:
- Add `isMangledIdent` to determine if `fmtIdent` would make any edits to the identifier
- Any function that has a mangled identifier is referred to using the mangled identifer
within the current file, but if it is exported the first export will be with the non-mangled name.
- Add `zig_import` to import a symbol under a different name
- Add a level of indirection to float function names. Now, they are referred to as
`zig_float_fn_<float type>_<operation>`. The definitions in zig.h are wrapped
with `zig_import` to import the symbol under the real name.
The specific problem that sparked this change was the combination of
`zig_libc_name_f80(name) __##name##x` with the input `fma`, resulting
in `__fmax`, which is a new intrinsic in recent versions of cl.exe.
With the above changes in place, compiler_rt can output the following:
```
static zig_weak_linkage_fn zig_f80 zig_e___fmax(zig_f80, zig_f80, zig_f80);
zig_export(zig_weak_linkage_fn zig_f80 zig_e___fmax(zig_f80, zig_f80, zig_f80), __fmax, "__fmax");
```
Within compiler_rt, `zig_e___fmax` is used to refer to the function, but consumers
will import `__fmax`, which maps to their `zig_float_fn_f80_fma` definition from zig.h.
* `CMakeLists.txt`: support the weird `uname -m` output.
* `CMakeLists.txt`: detect and use the C compiler's default arm mode.
* cbe: support gcc with both `f128` and `u128` emulated.
* std.os.linux.thumb: fix incorrectly passed asm inputs.
