Index: llvm/trunk/utils/gn/build/toolchain/BUILD.gn
===================================================================
--- llvm/trunk/utils/gn/build/toolchain/BUILD.gn
+++ llvm/trunk/utils/gn/build/toolchain/BUILD.gn
@@ -51,7 +51,7 @@
       # Remove the output file first so that ar doesn't try to modify the
       # existing file.
       command =
-          "rm -f {{output}} && ar rcsDT {{arflags}} -o {{output}} {{inputs}}"
+          "rm -f {{output}} && ar rcsDT {{arflags}} {{output}} {{inputs}}"
     }
     description = "AR {{output}}"
     outputs = [