This fixes a longstanding bug in compiler-builtins where C code was
compiled for the riscv targets but when distributed in rust-lang/rust
all the C code was actually compiled for x86_64 since there is no
configured C compiler for riscv. This was exposed by #286 by accident
but the underlying cause was somewhat unrelated.
For now we forcibly disable C code for riscv targets, and when the C
compiler story is sorted out in rust-lang/rust and with `cc-rs` we can
reenable. For now just use all the Rust definitions.
cc rust-lang/rust#60747
Looks like our tests weren't quite testing compiler-builtins when it was
compiled with unmangled symbols, so update the tests to catch this and
then fix the compilation of the `__clzsi2` intrinsic to use the C
version if it's compiled.
Looks like LLVM optimizes programs like:
fn foo(a: u8) -> f32 {
2.0f32.powf(a as f32)
}
to actually invoking `ldexpf`, so let's be sure to include bindings so
there's not undefined symbols.
It seems that the intrinsics that were generated for the functions in
example/intrinsics.rs where different implementations were given for
thumb6m-none-eabi target, have now been implemented in Rust so
configuration is not needed anymore.
Some files were not assembling for the Armv8-M Mainline architecture
profile with FPU extension. Reason being the same as for Armv7-M: the
conversion intrinsics including double precision floating
point variables do not work with single precision FPUs.
Also removes from exclusion files that are assembling without errors for
Armv7-M and Armv8-M Mainline.
Armv8-M Baseline, ie thumbv8m.base-none-eabi, is a superset of the
Armv6-M architecture profile. As it shares almost the same instruction
set, this commit copies the configuration for thumbv6m-none-eabi to
enable it.
Compilation on rustc 1.33.0-nightly (c76f3c374 2019-01-18) failed with
```
error: the feature `cfg_target_vendor` has been stable since 1.33.0 and no longer requires an attribute to enable
--> src/lib.rs:19:12
|
19 | #![feature(cfg_target_vendor)]
| ^^^^^^^^^^^^^^^^^
|
```
Removed the attribute to make it compile.
Alex Crichton
Goirad
John Kåre Alsaker
Hugues de Valon
Jordan Rhee
MikaelUrankar
Cyryl Płotnicki
Lokathor