Note that this changes semantics:
pub extern "C" fn __eqsf2(a: f32, b: f32) -> bool {
cmp(a, b).to_le_abi() != 0
}
is not the same as
pub extern "C" fn __eqsf2(a: f32, b: f32) -> i32 {
cmp(a, b).to_le_abi()
}
However, compiler-rt does the latter, so this is actually
an improvement.
E.g. take a look at the assembly output for:
pub fn comparesf2(a: f32, b: f32) -> bool { a > b }
pub fn comparedf2(a: f64, b: f64) -> bool { a > b }
which will include calls to __gtsf2 and __gtdf2.
Fix nightly CI
Currently we're getting lots of errors about duplicate lang items so deal with
this by `#[cfg_attr]`'ing off the lang item attribute in tests.
Remove mulsf3.c and muldf3.c from compiler-rt.
mulsf3 and muldf3 have Rust implementations since 8970485. This PR removes the C implementations to avoid conflicts.
Without this I wasn't able to compile the crate with the "c" feature enabled, the errors being
`multiple definition of '__muldf3'` and `multiple definition of '__mulsf3'`.
Use the "volatile" option and the "memory" clobber on inline asm that does
things like return directly, to reduce the chances of compilers rearranging
the code.
This commit prepares the build script for a wasm32 target that doesn't use
Emcripten, notably forcing the `mem` feature to get activated and forcibly
ignoring the `c` feature, even if activated, for the wasm32 target.
drop binfmt_misc dependency
Instead use the Cargo runner feature. The binfmt_misc approach requires running a privileged
container for setup. Not all docker setups support privileged containers so the test suite should be
more accessible with this change as no privileged container is needed.
r? @alexcrichton
Instead use the Cargo runner feature. The binfmt_misc approach requires running a privileged
container for setup. Not all docker setups support privileged containers so the test suite should be
more accessible with this change as no privileged container is needed.
Add atomic support for pre-ARMv6 on Linux
This uses the [kernel user helpers](https://www.kernel.org/doc/Documentation/arm/kernel_user_helpers.txt) which are available starting from kernel 2.6.15. Since Rust currently requires 2.6.18 at a minimum, this should be fine in practice. I did not include support for 64-bit atomics since that functionality is only available in kernel 3.1.
This PR allows Rust to work on older ARM versions such as ARMv4 and ARMv5 with the full libstd.
