Index: lib/Driver/Tools.cpp
===================================================================
--- lib/Driver/Tools.cpp
+++ lib/Driver/Tools.cpp
@@ -2107,6 +2107,9 @@
             TakeNextArg = true;
         } else if (Value.startswith("-gdwarf-")) {
           CmdArgs.push_back(Value.data());
+        } else if (Value == "-target-feature") {
+          CmdArgs.push_back("-target-feature");
+          TakeNextArg = true;
         } else {
           D.Diag(diag::err_drv_unsupported_option_argument)
             << A->getOption().getName() << Value;
Index: test/Driver/integrated-as.s
===================================================================
--- test/Driver/integrated-as.s
+++ test/Driver/integrated-as.s
@@ -43,3 +43,9 @@
 
 // RUN: %clang -### -c -integrated-as %s -Wa,-gdwarf-2 2>&1 | FileCheck --check-prefix=DWARF2WA %s
 // DWARF2WA: "-gdwarf-2"
+
+// RUN: %clang -### -c -integrated-as %s -Xassembler -target-feature -Xassembler -mp 2>&1 \
+// RUN:    | FileCheck --check-prefix=TARGET_FEATURE1 %s
+// RUN: %clang -### -c -integrated-as %s -Wa,-target-feature,-mp 2>&1 | FileCheck --check-prefix=TARGET_FEATURE1 %s
+// TARGET_FEATURE1: "-target-feature"
+// TARGET_FEATURE1: "-mp"