| Index: build/toolchain/mac/BUILD.gn
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| diff --git a/build/toolchain/mac/BUILD.gn b/build/toolchain/mac/BUILD.gn
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| index 056071491043e12951c9899d142f0a661f5d2778..18ee8b8cd9bd68d9e0c05e424f88dd75a50a529b 100644
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| --- a/build/toolchain/mac/BUILD.gn
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| +++ b/build/toolchain/mac/BUILD.gn
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| @@ -194,14 +194,17 @@ template("mac_clang_toolchain") {
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|      }
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|  
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|      toolchain_args() {
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| -      os = invoker.toolchain_os
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| +      current_os = invoker.toolchain_os
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| +
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| +      # TODO(dpranke): os is here for backwards compatibility.
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| +      os = current_os
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|      }
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|    }
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|  }
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|  
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|  # Toolchain representing the target build (either mac or iOS).
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|  mac_clang_toolchain("clang") {
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| -  toolchain_os = os
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| +  toolchain_os = current_os
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|  }
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|  
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|  # This toolchain provides a way for iOS target compiles to reference targets
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| 
 |