1 files changed, 9 insertions, 2 deletions
diff --git a/compiler/rustc_codegen_llvm/src/abi.rs b/compiler/rustc_codegen_llvm/src/abi.rs
index 043123fcab2..ac7583f5666 100644
--- a/compiler/rustc_codegen_llvm/src/abi.rs
+++ b/compiler/rustc_codegen_llvm/src/abi.rs
@@ -42,12 +42,13 @@ trait ArgAttributesExt {
 const ABI_AFFECTING_ATTRIBUTES: [(ArgAttribute, llvm::AttributeKind); 1] =
     [(ArgAttribute::InReg, llvm::AttributeKind::InReg)];
 
-const OPTIMIZATION_ATTRIBUTES: [(ArgAttribute, llvm::AttributeKind); 5] = [
+const OPTIMIZATION_ATTRIBUTES: [(ArgAttribute, llvm::AttributeKind); 6] = [
     (ArgAttribute::NoAlias, llvm::AttributeKind::NoAlias),
-    (ArgAttribute::NoCapture, llvm::AttributeKind::NoCapture),
+    (ArgAttribute::CapturesAddress, llvm::AttributeKind::CapturesAddress),
     (ArgAttribute::NonNull, llvm::AttributeKind::NonNull),
     (ArgAttribute::ReadOnly, llvm::AttributeKind::ReadOnly),
     (ArgAttribute::NoUndef, llvm::AttributeKind::NoUndef),
+    (ArgAttribute::CapturesReadOnly, llvm::AttributeKind::CapturesReadOnly),
 ];
 
 fn get_attrs<'ll>(this: &ArgAttributes, cx: &CodegenCx<'ll, '_>) -> SmallVec<[&'ll Attribute; 8]> {
@@ -83,6 +84,12 @@ fn get_attrs<'ll>(this: &ArgAttributes, cx: &CodegenCx<'ll, '_>) -> SmallVec<[&'
         }
         for (attr, llattr) in OPTIMIZATION_ATTRIBUTES {
             if regular.contains(attr) {
+                // captures(...) is only available since LLVM 21.
+                if (attr == ArgAttribute::CapturesReadOnly || attr == ArgAttribute::CapturesAddress)
+                    && llvm_util::get_version() < (21, 0, 0)
+                {
+                    continue;
+                }
                 attrs.push(llattr.create_attr(cx.llcx));
             }
         }