Index: clang/lib/Driver/ToolChains/CommonArgs.h
===================================================================
--- clang/lib/Driver/ToolChains/CommonArgs.h
+++ clang/lib/Driver/ToolChains/CommonArgs.h
@@ -94,6 +94,11 @@
 
 bool isUseSeparateSections(const llvm::Triple &Triple);
 
+/// \p EnvVar is split by system delimiter for environment variables.
+/// If \p ArgName is "-I", "-L", or an empty string, each entry from \p EnvVar
+/// is prefixed by \p ArgName then added to \p Args. Otherwise, for each
+/// entry of \p EnvVar, \p ArgName is added to \p Args first, then the entry
+/// itself is added.
 void addDirectoryList(const llvm::opt::ArgList &Args,
                       llvm::opt::ArgStringList &CmdArgs, const char *ArgName,
                       const char *EnvVar);
Index: clang/lib/Driver/ToolChains/CommonArgs.cpp
===================================================================
--- clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -91,7 +91,7 @@
     return; // Nothing to do.
 
   StringRef Name(ArgName);
-  if (Name.equals("-I") || Name.equals("-L"))
+  if (Name.equals("-I") || Name.equals("-L") || Name.empty())
     CombinedArg = true;
 
   StringRef Dirs(DirList);
Index: clang/lib/Driver/ToolChains/HIP.cpp
===================================================================
--- clang/lib/Driver/ToolChains/HIP.cpp
+++ clang/lib/Driver/ToolChains/HIP.cpp
@@ -327,7 +327,7 @@
        DriverArgs.getAllArgValues(options::OPT_hip_device_lib_path_EQ))
     LibraryPaths.push_back(DriverArgs.MakeArgString(Path));
 
-  addDirectoryList(DriverArgs, LibraryPaths, "-L", "HIP_DEVICE_LIB_PATH");
+  addDirectoryList(DriverArgs, LibraryPaths, "", "HIP_DEVICE_LIB_PATH");
 
   llvm::SmallVector<std::string, 10> BCLibs;
 
Index: clang/test/Driver/hip-device-libs.hip
===================================================================
--- clang/test/Driver/hip-device-libs.hip
+++ clang/test/Driver/hip-device-libs.hip
@@ -19,6 +19,13 @@
 // RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
 // RUN: 2>&1 | FileCheck %s --check-prefixes=COM,NOFLUSHD
 
+// Test environment variable HIP_DEVICE_LIB_PATH
+
+// RUN: HIP_DEVICE_LIB_PATH=%S/Inputs/hip_dev_lib \
+// RUN:   %clang -### -target x86_64-linux-gnu \
+// RUN:   -x hip --cuda-gpu-arch=gfx900 \
+// RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
+// RUN: 2>&1 | FileCheck %s --check-prefixes=COM
 
 // COM: {{"[^"]*clang[^"]*"}}
 // COM-SAME: "-mlink-builtin-bitcode" "{{.*}}hip.amdgcn.bc"