diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index b220e95..3f7ca99 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -2171,11 +2171,15 @@ void Generic_ELF::addClangTargetOptions(const ArgList &DriverArgs,
 
 /// Hexagon Toolchain
 
-std::string Hexagon_TC::GetGnuDir(const std::string &InstalledDir) {
+std::string Hexagon_TC::GetGnuDir(const std::string &InstalledDir,
+                                    const ArgList &Args) {
 
   // Locate the rest of the toolchain ...
-  if (strlen(GCC_INSTALL_PREFIX))
-    return std::string(GCC_INSTALL_PREFIX);
+  const Arg *A = Args.getLastArg(options::OPT_gcc_toolchain);
+  std::string gcc_toolchain( (A) ? A->getValue() : GCC_INSTALL_PREFIX);
+
+  if ( !gcc_toolchain.empty() )
+    return gcc_toolchain;
 
   std::string InstallRelDir = InstalledDir + "/../../gnu";
   if (llvm::sys::fs::exists(InstallRelDir))
@@ -2215,7 +2219,7 @@ static void GetHexagonLibraryPaths(
   const std::string MarchSuffix = "/" + MarchString;
   const std::string G0Suffix = "/G0";
   const std::string MarchG0Suffix = MarchSuffix + G0Suffix;
-  const std::string RootDir = Hexagon_TC::GetGnuDir(InstalledDir) + "/";
+  const std::string RootDir = Hexagon_TC::GetGnuDir(InstalledDir, Args) + "/";
 
   // lib/gcc/hexagon/...
   std::string LibGCCHexagonDir = RootDir + "lib/gcc/hexagon/";
@@ -2243,7 +2247,7 @@ Hexagon_TC::Hexagon_TC(const Driver &D, const llvm::Triple &Triple,
                        const ArgList &Args)
   : Linux(D, Triple, Args) {
   const std::string InstalledDir(getDriver().getInstalledDir());
-  const std::string GnuDir = Hexagon_TC::GetGnuDir(InstalledDir);
+  const std::string GnuDir = Hexagon_TC::GetGnuDir(InstalledDir, Args);
 
   // Note: Generic_GCC::Generic_GCC adds InstalledDir and getDriver().Dir to
   // program paths
@@ -2298,7 +2302,7 @@ void Hexagon_TC::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
     return;
 
   std::string Ver(GetGCCLibAndIncVersion());
-  std::string GnuDir = Hexagon_TC::GetGnuDir(D.InstalledDir);
+  std::string GnuDir = Hexagon_TC::GetGnuDir(D.InstalledDir, DriverArgs);
   std::string HexagonDir(GnuDir + "/lib/gcc/hexagon/" + Ver);
   addExternCSystemInclude(DriverArgs, CC1Args, HexagonDir + "/include");
   addExternCSystemInclude(DriverArgs, CC1Args, HexagonDir + "/include-fixed");
@@ -2314,7 +2318,7 @@ void Hexagon_TC::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs,
 
   const Driver &D = getDriver();
   std::string Ver(GetGCCLibAndIncVersion());
-  SmallString<128> IncludeDir(Hexagon_TC::GetGnuDir(D.InstalledDir));
+  SmallString<128> IncludeDir(Hexagon_TC::GetGnuDir(D.InstalledDir, DriverArgs));
 
   llvm::sys::path::append(IncludeDir, "hexagon/include/c++/");
   llvm::sys::path::append(IncludeDir, Ver);
diff --git a/lib/Driver/ToolChains.h b/lib/Driver/ToolChains.h
index 2c7ce06..d1dda49 100644
--- a/lib/Driver/ToolChains.h
+++ b/lib/Driver/ToolChains.h
@@ -710,7 +710,8 @@ public:
 
   StringRef GetGCCLibAndIncVersion() const { return GCCLibAndIncVersion.Text; }
 
-  static std::string GetGnuDir(const std::string &InstalledDir);
+  static std::string GetGnuDir(const std::string &InstalledDir,
+                               const llvm::opt::ArgList &Args);
 
   static StringRef GetTargetCPU(const llvm::opt::ArgList &Args);
 };
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index 559f30e..558736e 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -5213,8 +5213,8 @@ void hexagon::Link::ConstructJob(Compilation &C, const JobAction &JA,
   const std::string MarchSuffix = "/" + MarchString;
   const std::string G0Suffix = "/G0";
   const std::string MarchG0Suffix = MarchSuffix + G0Suffix;
-  const std::string RootDir = toolchains::Hexagon_TC::GetGnuDir(D.InstalledDir)
-                              + "/";
+  const std::string RootDir =
+      toolchains::Hexagon_TC::GetGnuDir(D.InstalledDir, Args) + "/";
   const std::string StartFilesDir = RootDir
                                     + "hexagon/lib"
                                     + (buildingLib
diff --git a/test/Driver/hexagon-toolchain-elf.c b/test/Driver/hexagon-toolchain-elf.c
index b25b974..984dc04 100644
--- a/test/Driver/hexagon-toolchain-elf.c
+++ b/test/Driver/hexagon-toolchain-elf.c
@@ -4,6 +4,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK001 %s
 // CHECK001: "-cc1" {{.*}} "-internal-externc-isystem" "{{.*}}/Inputs/hexagon_tree/qc/bin/../../gnu/lib/gcc/hexagon/4.4.0/include"
@@ -13,6 +14,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK002 %s
 // CHECK002: "-cc1" {{.*}} "-internal-isystem" "[[INSTALL_DIR:.*]]/Inputs/hexagon_tree/qc/bin/../../gnu{{/|\\\\}}hexagon/include/c++/4.4.0"
@@ -27,6 +29,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdinc \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK003 %s
@@ -38,6 +41,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdlibinc \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK004 %s
@@ -49,6 +53,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdlibinc \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK005 %s
@@ -61,6 +66,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdinc++ \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK006 %s
@@ -73,6 +79,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -march=hexagonv3 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK007 %s
@@ -82,6 +89,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -mcpu=hexagonv5 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK008 %s
@@ -91,6 +99,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -mv2 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK009 %s
@@ -100,6 +109,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK010 %s
 // CHECK010: "-cc1" {{.*}} "-target-cpu" "hexagonv4"
@@ -131,6 +141,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK011 %s
 // CHECK011: "-cc1"
@@ -155,6 +166,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clangxx -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK012 %s
 // CHECK012: "-cc1"
@@ -180,6 +192,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -Lone -L two -L three \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK013 %s
@@ -204,6 +217,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -static \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK014 %s
@@ -225,6 +239,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -shared \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK015 %s
@@ -254,6 +269,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -shared \
 // RUN:   -static \
 // RUN:   %s 2>&1 \
@@ -287,6 +303,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clangxx -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdlib \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK017 %s
@@ -313,6 +330,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostartfiles \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK018 %s
@@ -339,6 +357,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nodefaultlibs \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK019 %s
@@ -368,6 +387,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -moslib=first -moslib=second \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK020 %s
@@ -393,6 +413,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -moslib=first -moslib=second -moslib=standalone\
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK021 %s
@@ -421,6 +442,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clangxx -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -s \
 // RUN:   -Tbss 0xdead -Tdata 0xbeef -Ttext 0xcafe \
 // RUN:   -t \
@@ -453,6 +475,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK023 %s
 // CHECK023:      "-cc1"
@@ -464,16 +487,19 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -fpic \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK024 %s
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -fPIC \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK024 %s
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -fPIC \
 // RUN:   -msmall-data-threshold=8 \
 // RUN:   %s 2>&1 \
@@ -489,16 +515,19 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -G=8 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK025 %s
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -G 8 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK025 %s
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -msmall-data-threshold=8 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK025 %s
@@ -515,6 +544,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -pie \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK026 %s
@@ -525,6 +555,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -pie -shared \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK027 %s
@@ -538,6 +569,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK028 %s
 // CHECK028:      "-cc1"
@@ -551,6 +583,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-elf     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -gdwarf-2 \
 // RUN:   -Wa,--noexecstack,--trap \
 // RUN:   -Xassembler --keep-locals \
diff --git a/test/Driver/hexagon-toolchain.c b/test/Driver/hexagon-toolchain.c
index 384df80..391b78a 100644
--- a/test/Driver/hexagon-toolchain.c
+++ b/test/Driver/hexagon-toolchain.c
@@ -4,6 +4,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK001 %s
 // CHECK001: "-cc1" {{.*}} "-internal-externc-isystem" "{{.*}}/Inputs/hexagon_tree/qc/bin/../../gnu/lib/gcc/hexagon/4.4.0/include"
@@ -13,6 +14,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK002 %s
 // CHECK002: "-cc1" {{.*}} "-internal-isystem" "[[INSTALL_DIR:.*]]/Inputs/hexagon_tree/qc/bin/../../gnu{{/|\\\\}}hexagon/include/c++/4.4.0"
@@ -27,6 +29,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdinc \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK003 %s
@@ -38,6 +41,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdlibinc \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK004 %s
@@ -49,6 +53,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdlibinc \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK005 %s
@@ -61,6 +66,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdinc++ \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK006 %s
@@ -73,6 +79,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -march=hexagonv3 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK007 %s
@@ -82,6 +89,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -mcpu=hexagonv5 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK008 %s
@@ -91,6 +99,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -mv2 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK009 %s
@@ -100,6 +109,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK010 %s
 // CHECK010: "-cc1" {{.*}} "-target-cpu" "hexagonv4"
@@ -131,6 +141,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK011 %s
 // CHECK011: "-cc1"
@@ -155,6 +166,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clangxx -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK012 %s
 // CHECK012: "-cc1"
@@ -180,6 +192,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -Lone -L two -L three \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK013 %s
@@ -204,6 +217,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -static \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK014 %s
@@ -225,6 +239,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -shared \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK015 %s
@@ -254,6 +269,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -shared \
 // RUN:   -static \
 // RUN:   %s 2>&1 \
@@ -287,6 +303,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clangxx -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostdlib \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK017 %s
@@ -313,6 +330,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nostartfiles \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK018 %s
@@ -339,6 +357,7 @@
 
 // RUN: %clangxx -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -nodefaultlibs \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK019 %s
@@ -368,6 +387,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -moslib=first -moslib=second \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK020 %s
@@ -393,6 +413,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -moslib=first -moslib=second -moslib=standalone\
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK021 %s
@@ -421,6 +442,7 @@
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // RUN: %clangxx -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -s \
 // RUN:   -Tbss 0xdead -Tdata 0xbeef -Ttext 0xcafe \
 // RUN:   -t \
@@ -453,6 +475,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK023 %s
 // CHECK023:      "-cc1"
@@ -464,16 +487,19 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -fpic \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK024 %s
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -fPIC \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK024 %s
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -fPIC \
 // RUN:   -msmall-data-threshold=8 \
 // RUN:   %s 2>&1 \
@@ -489,16 +515,19 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -G=8 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK025 %s
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -G 8 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK025 %s
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -msmall-data-threshold=8 \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK025 %s
@@ -515,6 +544,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -pie \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK026 %s
@@ -525,6 +555,7 @@
 
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -pie -shared \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK027 %s
@@ -538,6 +569,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK028 %s
 // CHECK028:      "-cc1"
@@ -551,6 +583,7 @@
 // -----------------------------------------------------------------------------
 // RUN: %clang -### -target hexagon-unknown-linux     \
 // RUN:   -ccc-install-dir %S/Inputs/hexagon_tree/qc/bin \
+// RUN:   --gcc-toolchain="" \
 // RUN:   -gdwarf-2 \
 // RUN:   -Wa,--noexecstack,--trap \
 // RUN:   -Xassembler --keep-locals \