Index: lib/Driver/Driver.cpp
===================================================================
--- lib/Driver/Driver.cpp
+++ lib/Driver/Driver.cpp
@@ -1914,15 +1914,19 @@
                                options::OPT_m32, options::OPT_m16)) {
     llvm::Triple::ArchType AT = llvm::Triple::UnknownArch;
 
-    if (A->getOption().matches(options::OPT_m64))
+    if (A->getOption().matches(options::OPT_m64)) {
       AT = Target.get64BitArchVariant().getArch();
-    else if (A->getOption().matches(options::OPT_mx32) &&
+      if (Target.getEnvironment() == llvm::Triple::GNUX32)
+        Target.setEnvironment(llvm::Triple::GNU);
+    } else if (A->getOption().matches(options::OPT_mx32) &&
              Target.get64BitArchVariant().getArch() == llvm::Triple::x86_64) {
       AT = llvm::Triple::x86_64;
       Target.setEnvironment(llvm::Triple::GNUX32);
-    } else if (A->getOption().matches(options::OPT_m32))
+    } else if (A->getOption().matches(options::OPT_m32)) {
       AT = Target.get32BitArchVariant().getArch();
-    else if (A->getOption().matches(options::OPT_m16) &&
+      if (Target.getEnvironment() == llvm::Triple::GNUX32)
+        Target.setEnvironment(llvm::Triple::GNU);
+    } else if (A->getOption().matches(options::OPT_m16) &&
              Target.get32BitArchVariant().getArch() == llvm::Triple::x86) {
       AT = llvm::Triple::x86;
       Target.setEnvironment(llvm::Triple::CODE16);
Index: test/Driver/linux-ld.c
===================================================================
--- test/Driver/linux-ld.c
+++ test/Driver/linux-ld.c
@@ -250,6 +250,39 @@
 // CHECK-32-TO-X32: "-L[[SYSROOT]]/usr/lib"
 //
 // RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     --target=x86_64-unknown-linux-gnux32 -m64 \
+// RUN:     --sysroot=%S/Inputs/multilib_64bit_linux_tree \
+// RUN:   | FileCheck --check-prefix=CHECK-X32-TO-64 %s
+// CHECK-X32-TO-64: "{{.*}}ld{{(.exe)?}}" "--sysroot=[[SYSROOT:[^"]+]]"
+// CHECK-X32-TO-64: "{{.*}}/usr/lib/gcc/x86_64-unknown-linux/4.6.0{{/|\\\\}}crtbegin.o"
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0"
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/lib/../lib64"
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../lib64"
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/lib/../lib64"
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/usr/lib/../lib64"
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/lib"
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../.."
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/lib"
+// CHECK-X32-TO-64: "-L[[SYSROOT]]/usr/lib"
+//
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
+// RUN:     --target=x86_64-unknown-linux-gnux32 -m32 \
+// RUN:     --sysroot=%S/Inputs/multilib_64bit_linux_tree \
+// RUN:   | FileCheck --check-prefix=CHECK-X32-TO-32 %s
+// CHECK-X32-TO-32: "{{.*}}ld{{(.exe)?}}" "--sysroot=[[SYSROOT:[^"]+]]"
+// CHECK-X32-TO-32: "{{.*}}/usr/lib/gcc/x86_64-unknown-linux/4.6.0/32{{/|\\\\}}crtbegin.o"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/32"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/lib/../lib32"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../lib32"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/lib/../lib32"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/usr/lib/../lib32"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../../../x86_64-unknown-linux/lib"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/usr/lib/gcc/x86_64-unknown-linux/4.6.0/../../.."
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/lib"
+// CHECK-X32-TO-32: "-L[[SYSROOT]]/usr/lib"
+//
+// RUN: %clang -no-canonical-prefixes %s -### -o %t.o 2>&1 \
 // RUN:     --target=x86_64-unknown-linux -m32 \
 // RUN:     --gcc-toolchain=%S/Inputs/multilib_64bit_linux_tree/usr \
 // RUN:     --sysroot=%S/Inputs/multilib_32bit_linux_tree \