Index: polly/trunk/lib/External/CMakeLists.txt
===================================================================
--- polly/trunk/lib/External/CMakeLists.txt
+++ polly/trunk/lib/External/CMakeLists.txt
@@ -339,3 +339,9 @@
     COMPILE_FLAGS "-w"
   )
 endif ()
+
+if(MSVC)
+  # In the Windows API (with some exceptions), the maximum length for a path is
+  # MAX_PATH, which is defined as 260 characters. 
+  target_compile_definitions(PollyPPCG PUBLIC "-DPATH_MAX=260")
+endif ()