override run-time detection on mips msa tests

Author: gnzlbg

crates/simd-test-macro/src/lib.rs

@@ -57,13 +57,21 @@ pub fn simd_test(
         .expect(&format!("failed to parse name: {}", name.clone().as_str()));
 
     let target = env::var("TARGET").expect("TARGET environment variable not set");
+    let mut force_test = false;
     let macro_test = match target.split('-').next()
         .expect(&format!("target triple contained no \"-\": {}", target)) {
         "i686" | "x86_64" | "i586" => "is_x86_feature_detected",
         "arm" => "is_arm_feature_detected",
-        "aarch64" => "is_aarch64_feature_detected",
+        "aarch64" => "is_aarch64_feature_detected", 
         "powerpc64" => "is_powerpc64_feature_detected",
-        "mips64" | "mips64el" => "is_mips64_feature_detected",
+        "mips64" | "mips64el" => {
+            // On MIPS CI run-time feature detection always returns false due to
+            // this qemu bug: https://bugs.launchpad.net/qemu/+bug/1754372
+            //
+            // This is a workaround to force the MIPS tests to always run on CI.
+            force_test = true;
+            "is_mips64_feature_detected"
+        },
         t => panic!("unknown target: {}", t),
     };
     let macro_test = proc_macro2::Term::intern(macro_test);
@@ -85,7 +93,7 @@ pub fn simd_test(
         #[allow(non_snake_case)]
         #[test]
         fn #name() {
-            if #cfg_target_features {
+            if #force_test | (#cfg_target_features) {
                 return unsafe { #name() };
             } else {
                 ::stdsimd_test::assert_skip_test_ok(stringify!(#name));

stdsimd/arch/detect/linux/auxvec.rs

@@ -73,6 +73,7 @@ pub fn auxv() -> Result<AuxVec, ()> {
                 return Ok(AuxVec { hwcap });
             }
         }
+
         // Targets with AT_HWCAP and AT_HWCAP2:
         #[cfg(any(target_arch = "arm", target_arch = "powerpc64"))] {
             if let Ok(hwcap2) = getauxval(AT_HWCAP2) {
@@ -104,7 +105,6 @@ fn getauxval(key: usize) -> Result<usize, ()> {
             "getauxval\0".as_ptr() as *const _,
         );
         if ptr.is_null() {
-            eprintln!("getauxval was not linked");
             return Err(());
         }
 
@@ -127,7 +127,7 @@ fn auxv_from_file(file: &str) -> Result<AuxVec, ()> {
     {
         let raw: &mut [u8; 64 * mem::size_of::<usize>()] =
             unsafe { mem::transmute(&mut buf) };
-        file.read(raw).map_err(|e| { eprintln!("error reading /proc/self/auxv: {}", e); ()})?;
+        file.read(raw).map_err(|_| ())?;
     }
     auxv_from_buf(&buf)
 }
@@ -168,8 +168,6 @@ fn auxv_from_buf(buf: &[usize; 64]) -> Result<AuxVec, ()> {
         compile_error!("this function is not implemented for this target");
     }
 
-    eprintln!("error couldn't find key AT_HWCAP in file buffer");
-
     Err(())
 }
 
@@ -212,6 +210,9 @@ mod tests {
     }
 
 
+    // FIXME: on mips64 getauxval returns 0, and /proc/self/auxv
+    // does not always contain the AT_HWCAP key under qemu.
+    #[cfg(not(target_arch = "mips64"))]
     #[test]
     fn auxv_crate() {
         let v = auxv();