From 6a966a55ad376a266e31e5aac834fe055a51205a Mon Sep 17 00:00:00 2001 From: Sergey Fedorov Date: Mon, 15 Dec 2025 19:33:17 +0800 Subject: [PATCH] x86_64 target: 128-bit atomics is broken, default to 64-bit --- compiler/rustc_target/src/spec/x86_64_apple_darwin.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs b/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs index dc7597fe7b2..c4c9443cfb5 100644 --- a/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs +++ b/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs @@ -3,7 +3,7 @@ pub fn target() -> Target { let mut base = super::apple_base::opts("macos"); base.cpu = "core2".to_string(); - base.max_atomic_width = Some(128); // core2 support cmpxchg16b + base.max_atomic_width = Some(64); // core2 support cmpxchg16b, but LLVM produces broken code for it. base.eliminate_frame_pointer = false; base.pre_link_args.insert( LinkerFlavor::Gcc,