C++ API : Fixed compilation under GCC
C++ API : Fixed compilation under GCC

kornefalk/ocilib2017,Convey-Compliance/ocilib,vrogier/ocilib,lawrence200801/ocilib,kornefalk/ocilib2017,Convey-Compliance/ocilib,kornefalk/ocilib2017,alexeyvo/ocilib,ljx0305/ocilib,vrogier/ocilib,ljx0305/ocilib,alexeyvo/ocilib,ljx0305/ocilib,vrogier/ocilib,alexeyvo/ocilib,vrogier/ocilib,lawrence200801/ocilib,lawrence200801/ocilib,Convey-Compliance/ocilib