test no-core targets

Author: gnzlbg

build.rs

@@ -8,6 +8,7 @@ fn main() {
     let rustc_dep_of_std =
         std::env::var("CARGO_FEATURE_RUSTC_DEP_OF_STD").is_ok();
     let align_cargo_feature = std::env::var("CARGO_FEATURE_ALIGN").is_ok();
+    let test_no_core_build = std::env::var("RUST_LIBC_NO_CORE_BUILD").is_ok();
 
     // Rust >= 1.15 supports private module use:
     if rustc_minor_ver >= 15 || rustc_dep_of_std {
@@ -32,14 +33,18 @@ fn main() {
     // Rust >= 1.30 supports `core::ffi::c_void`, so libc can just re-export it.
     // Otherwise, it defines an incompatible type to retaining
     // backwards-compatibility.
-    if rustc_minor_ver >= 30 || rustc_dep_of_std {
+    if (rustc_minor_ver >= 30 || rustc_dep_of_std) && !test_no_core_build {
         println!("cargo:rustc-cfg=libc_core_cvoid");
     }
 
     // Rust >= 1.33 supports repr(packed(N))
     if rustc_minor_ver >= 33 || rustc_dep_of_std {
         println!("cargo:rustc-cfg=libc_packedN");
     }
+
+    if test_no_core_build {
+        println!("cargo:rustc-cfg=test_no_core_build");
+    }
 }
 
 fn rustc_minor_version() -> Option<u32> {

ci/build.sh

@@ -22,7 +22,7 @@ test_target() {
         opt="--release"
     fi
 
-    NO_STD=
+    NO_STD="${2}"
     case ${TARGET} in
         thumbv*)
             NO_STD=1
@@ -31,6 +31,10 @@ test_target() {
 
     rustup target add "${TARGET}" --toolchain "${RUST}" || true
 
+    if [ "$NO_CORE" = 1 ]; then
+        cargo "+${RUST}" build -vv $opt --no-default-features --target "${TARGET}"
+    fi
+
     # Test that libc builds without any default features (no libstd)
     cargo "+${RUST}" build -vv $opt --no-default-features --target "${TARGET}"
 
@@ -51,6 +55,48 @@ test_target() {
     fi
 }
 
+RUST_LINUX_NO_CORE_TARGETS="\
+x86_64-apple-darwin
+"
+
+for TARGET in $RUST_LINUX_NO_CORE_TARGETS; do
+    if [ "${RUST}" = "nightly" ]; then
+        RUST_LIBC_NO_CORE_BUILD=1 test_target "$TARGET" 1
+    fi
+done
+
+exit 0
+
+RUST_LINUX_NO_CORE_TARGETS="\
+aarch64-pc-windows-msvc \
+aarch64-unknown-cloudabi \
+armv7-unknown-cloudabi-eabihf \
+i586-pc-windows-msvc \
+i686-pc-windows-gnu \
+i686-pc-windows-msvc \
+i686-unknown-cloudabi \
+i686-unknown-haiku \
+i686-unknown-netbsd \
+mips-unknown-linux-uclib \
+mipsel-unknown-unknown-linux-uclib \
+nvptx64-nvidia-cuda \
+powerpc-unknown-linux-gnuspe \
+riscv32imac-unknown-none-elf \
+riscv32imc-unknown-none-elf \
+sparc-unknown-linux-gnu \
+sparc64-unknown-netbsd \
+thumbv8m.main-none-eabi \
+x86_64-pc-windows-gnu \
+x86_64-pc-windows-msvc
+x86_64-unknown-bitrig \
+x86_64-unknown-dragonfly \
+x86_64-unknown-haiku \
+x86_64-unknown-openbsd
+"
+
+
+exit 0
+
 RUST_LINUX_TARGETS="\
 aarch64-linux-android \
 aarch64-unknown-linux-gnu \
@@ -103,6 +149,12 @@ x86_64-unknown-cloudabi \
 
 RUST_NIGHTLY_LINUX_TARGETS="\
 aarch64-fuchsia \
+armv5te-unknown-linux-gnueabi \
+armv5te-unknown-linux-musleabi \
+armebv7r-none-eabi \
+armebv7r-none-eabihf \
+armv7r-none-eabi \
+armv7r-none-eabihf \
 thumbv6m-none-eabi \
 thumbv7em-none-eabi \
 thumbv7em-none-eabihf \

src/lib.rs

@@ -28,10 +28,14 @@
     not(any(
         feature = "use_std",
         feature = "rustc-dep-of-std",
-        cross_platform_docs
+        cross_platform_docs,
+        test_no_core_build
     )),
     no_std
 )]
+// Test no_core build
+#![cfg_attr(test_no_core_build, feature(no_core, lang_items))]
+#![cfg_attr(test_no_core_build, no_core)]
 
 #[cfg(all(not(cross_platform_docs), feature = "use_std"))]
 extern crate std as core;
@@ -50,7 +54,7 @@ cfg_if! {
 }
 
 cfg_if! {
-    if #[cfg(not(cross_platform_docs))] {
+    if #[cfg(not(any(cross_platform_docs, test_no_core_build)))] {
         cfg_if! {
             if #[cfg(libc_priv_mod_use)] {
                 #[cfg(libc_core_cvoid)]