When programming in PHP, webmaster can encounter an error with a message such as parse error:syntax error, unexpected $end. This error is related to a syntax error in PHP.

looks like it your php not understand : GMP syntax. its called return type declaration and was introduced for version 7.x So sest solution can be "use newer version php". if you use Oracle Enterprise ...

Didn't realise that was enabled by default in PHP (yet disabled by default in many common environments & distributions). This is now patched via 3d01759, to be part of the next patch release.