commit ec1461905b421cf0c56adeebb49bbf55bb33fd17
author Amanieu d'Antras <amanieu@gmail.com> Thu Mar 18 20:36:40 2021 +0000
committer Joshua Nelson <jyn514@gmail.com> Fri Apr 02 05:12:13 2021 -0400
tree 0d035ef6bba5e95538dfe6d141302c1a5e2bdb2c
parent 77e5b51164e50d6371fb3be80c36c3871cda4480

Fix building std_detect as a dependency of std (#1089)

crates/std_detect/Cargo.toml

diff --git a/crates/std_detect/Cargo.toml b/crates/std_detect/Cargo.toml
index 252e42c..4d0f93d 100644
--- a/crates/std_detect/Cargo.toml
+++ b/crates/std_detect/Cargo.toml
@@ -25,12 +25,22 @@
 libc = { version = "0.2", optional = true, default-features = false }
 cfg-if = "0.1.10"
 
+# When built as part of libstd
+core = { version = "1.0.0", optional = true, package = "rustc-std-workspace-core" }
+compiler_builtins = { version = "0.1.2", optional = true }
+alloc = { version = "1.0.0", optional = true, package = "rustc-std-workspace-alloc" }
+
 [dev-dependencies]
 auxv = "0.3.3"
 cupid = "0.6.0"
 
 [features]
 default = [ "std_detect_dlsym_getauxval", "std_detect_file_io" ]
-std_detect_file_io = []
+std_detect_file_io = [ "libc" ]
 std_detect_dlsym_getauxval = [ "libc" ]
-std_detect_env_override = []
+std_detect_env_override = [ "libc" ]
+rustc-dep-of-std = [
+    "core",
+    "compiler_builtins",
+    "alloc",
+]

crates/std_detect/src/detect/os/linux/auxvec.rs

diff --git a/crates/std_detect/src/detect/os/linux/auxvec.rs b/crates/std_detect/src/detect/os/linux/auxvec.rs
index d556b23..077fc9e 100644
--- a/crates/std_detect/src/detect/os/linux/auxvec.rs
+++ b/crates/std_detect/src/detect/os/linux/auxvec.rs
@@ -89,7 +89,7 @@
 
     #[cfg(not(feature = "std_detect_dlsym_getauxval"))]
     {
-        let hwcap = unsafe { libc::getauxval(AT_HWCAP) };
+        let hwcap = unsafe { libc::getauxval(AT_HWCAP as libc::c_ulong) as usize };
 
         // Targets with only AT_HWCAP:
         #[cfg(any(target_arch = "aarch64", target_arch = "mips", target_arch = "mips64"))]
@@ -106,7 +106,7 @@
             target_arch = "powerpc64"
         ))]
         {
-            let hwcap2 = unsafe { libc::getauxval(AT_HWCAP2) };
+            let hwcap2 = unsafe { libc::getauxval(AT_HWCAP2 as libc::c_ulong) as usize };
             if hwcap != 0 && hwcap2 != 0 {
                 return Ok(AuxVec { hwcap, hwcap2 });
             }

crates/std_detect/src/lib.rs

diff --git a/crates/std_detect/src/lib.rs b/crates/std_detect/src/lib.rs
index 46cf8fb..a5e09f7 100644
--- a/crates/std_detect/src/lib.rs
+++ b/crates/std_detect/src/lib.rs
@@ -20,6 +20,7 @@
 #![cfg_attr(feature = "std_detect_file_io", feature(vec_spare_capacity))]
 #![no_std]
 
+#[cfg_attr(feature = "rustc-dep-of-std", allow(unused_extern_crates))]
 #[cfg(feature = "std_detect_file_io")]
 extern crate alloc;