diff --git a/include/ghc/filesystem.hpp b/include/ghc/filesystem.hpp
index 4ec6e08..02a6553 100644
--- a/include/ghc/filesystem.hpp
+++ b/include/ghc/filesystem.hpp
@@ -255,6 +255,10 @@
 #include <experimental/string_view>
 #endif
 
+#if !defined(GHC_OS_WINDOWS) && !defined(PATH_MAX)
+#define PATH_MAX 4096
+#endif
+
 //- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 // Behaviour Switches (see README.md, should match the config in test/filesystem_test.cpp):
 //- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -302,7 +306,7 @@
 //- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
 // ghc::filesystem version in decimal (major * 10000 + minor * 100 + patch)
-#define GHC_FILESYSTEM_VERSION 10510L
+#define GHC_FILESYSTEM_VERSION 10511L
 
 #if !defined(GHC_WITH_EXCEPTIONS) && (defined(__EXCEPTIONS) || defined(__cpp_exceptions) || defined(_CPPUNWIND))
 #define GHC_WITH_EXCEPTIONS