Building-MFIX-with-CSG-EB-on-Spock.md

@@ -43,6 +43,31 @@ zlib/1.2.11
 
 first to see which conan packages are already built (and cached) on your system
 
+## Patch PEGTL [experimental/]filesystem (for pre-C++17 compiler)
+
+Workaround for compiler not supporting C++17
+
+In file:
+```
+~/.conan/data/taocpp-pegtl/3.2.1/_/_/package/5ab84d6acfe1f23c4fae0ab88f26e3a396351ac9/include/tao/pegtl/internal/filesystem.hpp
+```
+
+change ~ line 47 from
+
+```
+#include <filesystem>
+to
+#include <experimental/filesystem>
+```
+
+and then change ~ line 51 from
+
+```
+   namespace filesystem = ::std::filesystem;
+to
+   namespace filesystem = std::experimental::filesystem;
+```
+
 ## Build Conan CSG-EB package
 
 ```