MSVC: compat: dirname() from <libgen.h>
diff --git a/CMakeModules/UseCompat.cmake b/CMakeModules/UseCompat.cmake
index 753b10d..eb4b103 100644
--- a/CMakeModules/UseCompat.cmake
+++ b/CMakeModules/UseCompat.cmake
@@ -55,6 +55,7 @@
     check_symbol_exists(localtime_r "time.h" HAVE_LOCALTIME_R)
     check_symbol_exists(strptime "time.h" HAVE_STRPTIME)
     check_symbol_exists(mmap "sys/mman.h" HAVE_MMAP)
+    check_symbol_exists(dirname "libgen.h" HAVE_DIRNAME)
 
     unset(CMAKE_REQUIRED_DEFINITIONS)
     unset(CMAKE_REQUIRED_LIBRARIES)