Don't always enabled CPU features

Author: antoyo

src/base.rs

@@ -103,29 +103,22 @@ pub fn compile_codegen_unit(tcx: TyCtxt<'_>, cgu_name: Symbol, target_info: Arc<
             .collect();
 
         let add_cpu_feature_flag = |feature: &str| {
-            // FIXME(antoyo): some tests cause a segfault in GCC when not enabling all these
-            // features.
-            if (true || target_info.cpu_supports(feature)) && !disabled_features.contains(feature) {
+            if target_info.cpu_supports(feature) && !disabled_features.contains(feature) {
                 context.add_command_line_option(&format!("-m{}", feature));
             }
         };
 
         // TODO(antoyo): only set on x86 platforms.
         context.add_command_line_option("-masm=intel");
 
-        let features = ["sse2", "avx", "avx2", "sha", "fma", "gfni", "f16c", "aes", "bmi2", "rtm",
+        let features = ["64", "bmi", "sse2", "avx", "avx2", "sha", "fma", "fma4", "gfni", "f16c", "aes", "bmi2", "pclmul", "rtm",
             "vaes", "vpclmulqdq", "xsavec",
         ];
 
         for feature in &features {
             add_cpu_feature_flag(feature);
         }
 
-        // TODO(antoyo): only add the following cli arguments if the feature is supported.
-        context.add_command_line_option("-mpclmul");
-        context.add_command_line_option("-mfma4");
-        context.add_command_line_option("-m64");
-        context.add_command_line_option("-mbmi");
         //context.add_command_line_option("-mavxvnni"); // The CI doesn't support this option.
 
         for arg in &tcx.sess.opts.cg.llvm_args {

src/lib.rs

@@ -313,7 +313,7 @@ pub fn __rustc_codegen_backend() -> Box<dyn CodegenBackend> {
 
         // Get the second TargetInfo with the correct CPU features by setting the arch.
         let context = Context::default();
-        context.add_driver_option(&format!("-march={}", arch.to_str().unwrap()));
+        context.add_command_line_option(&format!("-march={}", arch.to_str().unwrap()));
         Arc::new(context.get_target_info())
     };
     #[cfg(not(feature="master"))]