Index: include/clang/Driver/CC1Options.td
===================================================================
--- include/clang/Driver/CC1Options.td
+++ include/clang/Driver/CC1Options.td
@@ -178,7 +178,7 @@
   HelpText<"The string to embed in the .LLVM.command.line section.">;
 def compress_debug_sections : Flag<["-", "--"], "compress-debug-sections">,
     HelpText<"DWARF debug sections compression">;
-def compress_debug_sections_EQ : Joined<["-"], "compress-debug-sections=">,
+def compress_debug_sections_EQ : Joined<["--"], "compress-debug-sections=">,
     HelpText<"DWARF debug sections compression type">;
 def mno_exec_stack : Flag<["-"], "mnoexecstack">,
   HelpText<"Mark the file as not needing an executable stack">;
Index: lib/Driver/ToolChains/Clang.cpp
===================================================================
--- lib/Driver/ToolChains/Clang.cpp
+++ lib/Driver/ToolChains/Clang.cpp
@@ -1007,7 +1007,7 @@
   if (checkDebugInfoOption(A, Args, D, TC)) {
     if (A->getOption().getID() == options::OPT_gz) {
       if (llvm::zlib::isAvailable())
-        CmdArgs.push_back("-compress-debug-sections");
+        CmdArgs.push_back("--compress-debug-sections");
       else
         D.Diag(diag::warn_debug_compression_unavailable);
       return;
@@ -1015,11 +1015,11 @@
 
     StringRef Value = A->getValue();
     if (Value == "none") {
-      CmdArgs.push_back("-compress-debug-sections=none");
+      CmdArgs.push_back("--compress-debug-sections=none");
     } else if (Value == "zlib" || Value == "zlib-gnu") {
       if (llvm::zlib::isAvailable()) {
         CmdArgs.push_back(
-            Args.MakeArgString("-compress-debug-sections=" + Twine(Value)));
+            Args.MakeArgString("--compress-debug-sections=" + Twine(Value)));
       } else {
         D.Diag(diag::warn_debug_compression_unavailable);
       }
Index: lib/Driver/ToolChains/Gnu.cpp
===================================================================
--- lib/Driver/ToolChains/Gnu.cpp
+++ lib/Driver/ToolChains/Gnu.cpp
@@ -627,14 +627,12 @@
 
   if (const Arg *A = Args.getLastArg(options::OPT_gz, options::OPT_gz_EQ)) {
     if (A->getOption().getID() == options::OPT_gz) {
-      CmdArgs.push_back("-compress-debug-sections");
+      CmdArgs.push_back("--compress-debug-sections");
     } else {
       StringRef Value = A->getValue();
-      if (Value == "none") {
-        CmdArgs.push_back("-compress-debug-sections=none");
-      } else if (Value == "zlib" || Value == "zlib-gnu") {
+      if (Value == "none" || Value == "zlib" || Value == "zlib-gnu") {
         CmdArgs.push_back(
-            Args.MakeArgString("-compress-debug-sections=" + Twine(Value)));
+            Args.MakeArgString("--compress-debug-sections=" + Twine(Value)));
       } else {
         D.Diag(diag::err_drv_unsupported_option_argument)
             << A->getOption().getName() << Value;
Index: test/Driver/compress-noias.c
===================================================================
--- test/Driver/compress-noias.c
+++ test/Driver/compress-noias.c
@@ -17,19 +17,19 @@
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
-// CHECK-OPT_GZ: "-compress-debug-sections"
+// CHECK-OPT_GZ: "--compress-debug-sections"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=none -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=none -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
-// CHECK-OPT_GZ_EQ_NONE: "-compress-debug-sections=none"
+// CHECK-OPT_GZ_EQ_NONE: "--compress-debug-sections=none"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
-// CHECK-OPT_GZ_EQ_ZLIB: "-compress-debug-sections=zlib"
+// CHECK-OPT_GZ_EQ_ZLIB: "--compress-debug-sections=zlib"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib-gnu -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=zlib-gnu -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
-// CHECK-OPT_GZ_EQ_ZLIB_GNU: "-compress-debug-sections=zlib-gnu"
+// CHECK-OPT_GZ_EQ_ZLIB_GNU: "--compress-debug-sections=zlib-gnu"
 
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=invalid -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
 // RUN: %clang -### -target i686-unknown-linux-gnu -fno-integrated-as -gz=invalid -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
Index: test/Driver/compress.c
===================================================================
--- test/Driver/compress.c
+++ test/Driver/compress.c
@@ -16,19 +16,19 @@
 
 // RUN: %clang -### -fintegrated-as -gz -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
 // RUN: %clang -### -fintegrated-as -gz -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ %s
-// CHECK-OPT_GZ: "-compress-debug-sections"
+// CHECK-OPT_GZ: "--compress-debug-sections"
 
 // RUN: %clang -### -fintegrated-as -gz=none -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
 // RUN: %clang -### -fintegrated-as -gz=none -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_NONE %s
-// CHECK-OPT_GZ_EQ_NONE: "-compress-debug-sections=none"
+// CHECK-OPT_GZ_EQ_NONE: "--compress-debug-sections=none"
 
 // RUN: %clang -### -fintegrated-as -gz=zlib -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
 // RUN: %clang -### -fintegrated-as -gz=zlib -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB %s
-// CHECK-OPT_GZ_EQ_ZLIB: "-compress-debug-sections=zlib"
+// CHECK-OPT_GZ_EQ_ZLIB: "--compress-debug-sections=zlib"
 
 // RUN: %clang -### -fintegrated-as -gz=zlib-gnu -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
 // RUN: %clang -### -fintegrated-as -gz=zlib-gnu -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_ZLIB_GNU %s
-// CHECK-OPT_GZ_EQ_ZLIB_GNU: "-compress-debug-sections=zlib-gnu"
+// CHECK-OPT_GZ_EQ_ZLIB_GNU: "--compress-debug-sections=zlib-gnu"
 
 // RUN: %clang -### -fintegrated-as -gz=invalid -x assembler -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s
 // RUN: %clang -### -fintegrated-as -gz=invalid -c %s 2>&1 | FileCheck -check-prefix CHECK-OPT_GZ_EQ_INVALID %s