diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index d8284040eb3be4c157309a30588b21b65de94479..253a083109c1e4675e351ad58787bf787a5cbffc 100644
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -1911,19 +1911,14 @@ static llvm::Triple computeTargetTriple(StringRef DefaultTargetTriple,
     return Target;
 
   // Handle pseudo-target flags '-m32' and '-m64'.
-  // FIXME: Should this information be in llvm::Triple?
   if (Arg *A = Args.getLastArg(options::OPT_m32, options::OPT_m64)) {
-    if (A->getOption().matches(options::OPT_m32)) {
-      if (Target.getArch() == llvm::Triple::x86_64)
-        Target.setArch(llvm::Triple::x86);
-      if (Target.getArch() == llvm::Triple::ppc64)
-        Target.setArch(llvm::Triple::ppc);
-    } else {
-      if (Target.getArch() == llvm::Triple::x86)
-        Target.setArch(llvm::Triple::x86_64);
-      if (Target.getArch() == llvm::Triple::ppc)
-        Target.setArch(llvm::Triple::ppc64);
-    }
+    llvm::Triple::ArchType AT;
+    if (A->getOption().matches(options::OPT_m32))
+      AT = Target.get32BitArchVariant().getArch();
+    else
+      AT = Target.get64BitArchVariant().getArch();
+    if (AT != llvm::Triple::UnknownArch)
+      Target.setArch(AT);
   }
 
   return Target;
diff --git a/test/Driver/unknown-gcc-arch.c b/test/Driver/unknown-gcc-arch.c
index 184443b08cb7fa5da288ec281a3ec6fb943a853f..dd2c96ac8b83577c294b2104b6ff4dfb11517788 100644
--- a/test/Driver/unknown-gcc-arch.c
+++ b/test/Driver/unknown-gcc-arch.c
@@ -30,3 +30,11 @@
 // RUN: %clang -target powerpc-unknown-unknown -c -x assembler %s -### -m64 2>&1 \
 // RUN:   | FileCheck -check-prefix=PPC-M64 %s
 // PPC-M64: {{.*as.*-a64}}
+
+// RUN: %clang -target sparc64-unknown-unknown -no-integrated-as -c -x assembler %s -### -m32 2>&1 \
+// RUN:   | FileCheck -check-prefix=SPARCV8 %s
+// SPARCV8: {{.*as.*-32}}
+
+// RUN: %clang -target sparc-unknown-unknown -no-integrated-as -c -x assembler %s -### -m64 2>&1 \
+// RUN:   | FileCheck -check-prefix=SPARCV9 %s
+// SPARCV9: {{.*as.*-64}}