Index: llvm-toolchain-snapshot_9~svn351647/clang/lib/Basic/FileManager.cpp
===================================================================
--- llvm-toolchain-snapshot_9~svn351647.orig/clang/lib/Basic/FileManager.cpp
+++ llvm-toolchain-snapshot_9~svn351647/clang/lib/Basic/FileManager.cpp
@@ -495,6 +495,12 @@ void FileManager::invalidateCache(const
   UniqueRealFiles.erase(Entry->getUniqueID());
 }
 
+// For GNU Hurd
+#if defined(__GNU__) && !defined(PATH_MAX)
+# define PATH_MAX 4096
+#endif
+
+
 void FileManager::GetUniqueIDMapping(
                    SmallVectorImpl<const FileEntry *> &UIDToFiles) const {
   UIDToFiles.clear();
Index: llvm-toolchain-snapshot_9~svn351647/lldb/include/lldb/lldb-defines.h
===================================================================
--- llvm-toolchain-snapshot_9~svn351647.orig/lldb/include/lldb/lldb-defines.h
+++ llvm-toolchain-snapshot_9~svn351647/lldb/include/lldb/lldb-defines.h
@@ -27,6 +27,11 @@
 #define INT32_MAX 2147483647
 #endif
 
+// For GNU Hurd
+#if defined(__GNU__) && !defined(PATH_MAX)
+# define PATH_MAX 4096
+#endif
+
 #if !defined(UINT32_MAX)
 #define UINT32_MAX 4294967295U
 #endif
Index: llvm-toolchain-snapshot_9~svn351647/tools/dsymutil/DwarfLinker.cpp
===================================================================
--- llvm-toolchain-snapshot_9~svn351647.orig/tools/dsymutil/DwarfLinker.cpp
+++ llvm-toolchain-snapshot_9~svn351647/tools/dsymutil/DwarfLinker.cpp
@@ -100,6 +100,11 @@
 #include <utility>
 #include <vector>
 
+// For GNU Hurd
+#if defined(__GNU__) && !defined(PATH_MAX)
+# define PATH_MAX 4096
+#endif
+
 namespace llvm {
 namespace dsymutil {
 
Index: llvm-toolchain-snapshot_9~svn351647/polly/lib/External/ppcg/cuda_common.c
===================================================================
--- llvm-toolchain-snapshot_9~svn351647.orig/polly/lib/External/ppcg/cuda_common.c
+++ llvm-toolchain-snapshot_9~svn351647/polly/lib/External/ppcg/cuda_common.c
@@ -15,6 +15,11 @@
 #include "cuda_common.h"
 #include "ppcg.h"
 
+// For GNU Hurd
+#if defined(__GNU__) && !defined(PATH_MAX)
+# define PATH_MAX 4096
+#endif
+
 /* Open the host .cu file and the kernel .hu and .cu files for writing.
  * Add the necessary includes.
  */
Index: llvm-toolchain-snapshot_9~svn351647/clang/lib/Frontend/ModuleDependencyCollector.cpp
===================================================================
--- llvm-toolchain-snapshot_9~svn351647.orig/clang/lib/Frontend/ModuleDependencyCollector.cpp
+++ llvm-toolchain-snapshot_9~svn351647/clang/lib/Frontend/ModuleDependencyCollector.cpp
@@ -98,6 +98,11 @@ struct ModuleDependencyMMCallbacks : pub
 
 }
 
+// For GNU Hurd
+#if defined(__GNU__) && !defined(PATH_MAX)
+# define PATH_MAX 4096
+#endif
+
 // TODO: move this to Support/Path.h and check for HAVE_REALPATH?
 static bool real_path(StringRef SrcPath, SmallVectorImpl<char> &RealPath) {
 #ifdef LLVM_ON_UNIX