diff --git a/swift/internal/swift_autoconfiguration.bzl b/swift/internal/swift_autoconfiguration.bzl
index 05593d3eb..51efe1451 100644
--- a/swift/internal/swift_autoconfiguration.bzl
+++ b/swift/internal/swift_autoconfiguration.bzl
@@ -283,6 +283,21 @@ alias(
 )
         """)
 
+def _toolchain_overriden_tools(toolchain_root, extension = ""):
+    tools = {
+        "ld": toolchain_root.get_child("lld" + extension),
+        "llvm-cov": toolchain_root.get_child("llvm-cov" + extension),
+        "llvm-profdata": toolchain_root.get_child("llvm-profdata" + extension),
+        "cpp": toolchain_root.get_child("clang-cpp" + extension),
+        "gcc": toolchain_root.get_child("clang" + extension),
+    }
+
+    # llvm-ar is not shipped before Swift 5.8
+    ar = toolchain_root.get_child("llvm-ar" + extension)
+    if ar.exists:
+        tools["ar"] = ar
+    return tools
+
 def _create_linux_cc_toolchain(repository_ctx):
     """Creates BUILD targets for the Swift-provided C++ toolchain on Linux.
 
@@ -292,14 +307,7 @@ def _create_linux_cc_toolchain(repository_ctx):
 
     toolchain_root = _toolchain_root(repository_ctx)
     cpu = get_cpu_value(repository_ctx)
-    configure_unix_toolchain(repository_ctx, cpu, overriden_tools = {
-        "ar": toolchain_root.get_child("llvm-ar"),
-        "ld": toolchain_root.get_child("lld"),
-        "llvm-cov": toolchain_root.get_child("llvm-cov"),
-        "llvm-profdata": toolchain_root.get_child("llvm-profdata"),
-        "cpp": toolchain_root.get_child("clang-cpp"),
-        "gcc": toolchain_root.get_child("clang"),
-    })
+    configure_unix_toolchain(repository_ctx, cpu, overriden_tools = _toolchain_overriden_tools(toolchain_root))
 
 def _create_windows_cc_toolchain(repository_ctx):
     """Creates BUILD targets for the Swift-provided C++ toolchain on Windows.
@@ -309,14 +317,7 @@ def _create_windows_cc_toolchain(repository_ctx):
     """
 
     toolchain_root = _toolchain_root(repository_ctx)
-    configure_windows_toolchain(repository_ctx, overriden_tools = {
-        "ar": toolchain_root.get_child("llvm-ar.exe"),
-        "ld": toolchain_root.get_child("lld.exe"),
-        "llvm-cov": toolchain_root.get_child("llvm-cov.exe"),
-        "llvm-profdata": toolchain_root.get_child("llvm-profdata.exe"),
-        "cpp": toolchain_root.get_child("clang-cpp.exe"),
-        "gcc": toolchain_root.get_child("clang.exe"),
-    })
+    configure_windows_toolchain(repository_ctx, overriden_tools = _toolchain_overriden_tools(toolchain_root, ".exe"))
 
 def _create_linux_toolchain(repository_ctx):
     """Creates BUILD targets for the Swift toolchain on Linux.