The overflow check for safe signed subtraction was using the formula (rhs < 0) == (lhs > result). This logic is flawed and incorrectly reports an overflow when the right-hand side is zero.
For the expression 42 - 0, this check evaluated to (0 < 0) == (42 > 42), which is false == false, resulting in true. This caused the generated SPIR-V to incorrectly branch to an OpUnreachable instruction, preventing the result from being stored.
Fixes#24281.
* resinator: Only preprocess when the input is an .rc file
* resinator: Fix include directory detection when cross-compiling from certain host archs
Previously, resinator would use the host arch as the target arch when looking for windows-gnu include directories. However, Zig only thinks it can provide a libc for targets specified in the `std.zig.target.available_libcs` array, which only includes a few for windows-gnu. Therefore, when cross-compiling from a host architecture that doesn't have a windows-gnu target in the available_libcs list, resinator would fail to detect the MinGW include directories.
Now, the custom option `/:target` is passed to `zig rc` which is intended for the COFF object file target, but can be re-used for the include directory target as well. For the include directory target, resinator will convert the MachineType to the relevant arch, or fail if there is no equivalent arch/no support for detecting the includes for the MachineType (currently 64-bit Itanium and EBC).
Fixes the `windows_resources` standalone test failing when the host is, for example, `riscv64-linux`.
Previously, resinator would use the host arch as the target arch when looking for windows-gnu include directories. However, Zig only thinks it can provide a libc for targets specified in the `std.zig.target.available_libcs` array, which only includes a few for windows-gnu. Therefore, when cross-compiling from a host architecture that doesn't have a windows-gnu target in the available_libcs list, resinator would fail to detect the MinGW include directories.
Now, the custom option `/:target` is passed to `zig rc` which is intended for the COFF object file target, but can be re-used for the include directory target as well. For the include directory target, resinator will convert the MachineType to the relevant arch, or fail if there is no equivalent arch/no support for detecting the includes for the MachineType (currently 64-bit Itanium and EBC).
Fixes the `windows_resources` standalone test failing when the host is, for example, `riscv64-linux`.
* Fix warning WasmMut_toC not all control paths return a value
This is a follow up to https://github.com/ziglang/zig/pull/24206 where
I had previously submitted different mechanisms to fix this warning.
This PR is a suggestion by Alex to return NULL instead and Andrew
confirmed this is his preference.
* c.darwin: define MSG for macos
* darwin: add series os name
* Update lib/std/c.zig
Co-authored-by: Alex Rønne Petersen <alex@alexrp.com>
---------
Co-authored-by: Alex Rønne Petersen <alex@alexrp.com>
Btrfs at least supports 16 EiB files (limited in practice to 8EiB by the
Linux VFS code which uses signed 64-bit offsets). So fix the fs.zig test
case to expect either a FileTooBig or success from truncating a file to
8EiB. And test that beyond that size the offset is interpreted as a
negative number.
Fixes#24242
musl and glibc both specify r0 as an output register because its value
may be overwritten by system calls. As with the updates for 64-bit
PowerPC in the previous commit, this commit brings Zig's syscall
functions for 32-bit PowerPC in line with musl and glibc by adding r0 to
the list of clobbers. (Listing r0 as both an input and a clobber is as
close as we can get to musl, which declares it as a "+r" read-write
output, since Zig doesn't support multiple outputs or the "+"
specifier.)
On powerpc64le Linux, the registers used for passing syscall parameters
(r4-r8, as well as r0 for the syscall number) are volatile, or
caller-saved. However, Zig's syscall wrappers for this architecture do
not include all such registers in the list of clobbers, leading the
compiler to assume these registers will maintain their values after the
syscall completes.
In practice, this resulted in a segfault when allocating memory with
`std.heap.SmpAllocator`, which calls `std.os.linux.sched_getaffinity`.
The third parameter to `sched_getaffinity` is a pointer to a `cpu_set_t`
and is stored in register r5. After the syscall, the code attempts to
access data in the `cpu_set_t`, but because the compiler doesn't realize
the value of r5 may have changed, it uses r5 as the memory address, which
in practice resulted in a memory access at address 0x8.
This commit adds all volatile registers to the list of clobbers.
