error: unknown type name 'char16_t'

[professor]

I'm compiling on mac OS X 10.11.6 El Capitan.
I'm using xerces-c version 3.2.1

I'm following the steps listed here: https://github.com/greenplum-db/gpdb

I'm seeing two types of error:

In file included from /usr/local/include/xercesc/util/XercesDefs.hpp:46:
/usr/local/include/xercesc/util/Xerces_autoconf_config.hpp:122:9: error: unknown type name 'char16_t'
typedef XERCES_XMLCH_T                          XMLCh;
        ^
/usr/local/include/xercesc/util/Xerces_autoconf_config.hpp:66:24: note: expanded from macro 'XERCES_XMLCH_T'
#define XERCES_XMLCH_T char16_t

In file included from /usr/local/include/xercesc/internal/XSerializable.hpp:25:
/usr/local/include/xercesc/internal/XSerializeEngine.hpp:486:30: error: class member cannot be redeclared
           XSerializeEngine& operator<<(int);
                             ^
/usr/local/include/xercesc/internal/XSerializeEngine.hpp:482:30: note: previous declaration is here
           XSerializeEngine& operator<<(XMLCh);
                             ^
/usr/local/include/xercesc/internal/XSerializeEngine.hpp:514:30: error: class member cannot be redeclared
           XSerializeEngine& operator>>(int&);
                             ^
/usr/local/include/xercesc/internal/XSerializeEngine.hpp:510:30: note: previous declaration is here
           XSerializeEngine& operator>>(XMLCh&);
                             ^

This is for v2.55.5

I'll try this on a brand new machine soon.

[hsyuan]

use lower version. 3.1.1 or 3.1.2

[d]

I tried building GPDB with ORCA on an iMac (running 10.13 "High Sierra") and I cannot reproduce this problem ... The xerces-c I tried with was a straight-up brew install xerces-c

[d]

I have a hunch now, digging deeper before I can post more. Basically I have a build error on a pre-release version of Ubuntu 18.04 that is seemingly related to Xerces 3.2.