Prepare this crate for more wasm32 compatibility

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.
This commit is contained in:
Alex Crichton 2017-10-24 17:03:39 -07:00
parent 2d414afec5
commit 45cd956acc
2 changed files with 16 additions and 6 deletions

View File

@ -12,6 +12,12 @@ fn main() {
return;
}
// Forcibly enable memory intrinsics on wasm32 as we don't have a libc to
// provide them.
if target.contains("wasm32") {
println!("cargo:rustc-cfg=feature=\"mem\"");
}
// NOTE we are going to assume that llvm-target, what determines our codegen option, matches the
// target triple. This is usually correct for our built-in targets but can break in presence of
// custom targets, which can have arbitrary names.
@ -25,9 +31,13 @@ fn main() {
// mangling names though we assume that we're also in test mode so we don't
// build anything and we rely on the upstream implementation of compiler-rt
// functions
if !cfg!(feature = "mangled-names") {
#[cfg(feature = "c")]
c::compile(&llvm_target);
if !cfg!(feature = "mangled-names") && cfg!(feature = "c") {
// no C compiler for wasm
if !target.contains("wasm32") {
#[cfg(feature = "c")]
c::compile(&llvm_target);
println!("cargo:rustc-cfg=use_c");
}
}
// To compile intrinsics.rs for thumb targets, where there is no libc

View File

@ -31,7 +31,7 @@
/// A quick overview of attributes supported right now are:
///
/// * `use_c_shim_if` - takes a #[cfg] directive and falls back to the
/// C-compiled version if `feature = "c"` is specified.
/// C-compiled version if `use_c` is specified.
/// * `aapcs_on_arm` - forces the ABI of the function to be `"aapcs"` on ARM and
/// the specified ABI everywhere else.
/// * `unadjusted_on_win64` - like `aapcs_on_arm` this switches to the
@ -68,7 +68,7 @@ macro_rules! intrinsics {
$($rest:tt)*
) => (
#[cfg(all(feature = "c", $($cfg_clause)*))]
#[cfg(all(use_c, $($cfg_clause)*))]
pub extern $abi fn $name( $($argname: $ty),* ) -> $ret {
extern $abi {
fn $name($($argname: $ty),*) -> $ret;
@ -78,7 +78,7 @@ macro_rules! intrinsics {
}
}
#[cfg(not(all(feature = "c", $($cfg_clause)*)))]
#[cfg(not(all(use_c, $($cfg_clause)*)))]
intrinsics! {
$(#[$($attr)*])*
pub extern $abi fn $name( $($argname: $ty),* ) -> $ret {