C API: Fix #49 (compilation under VS2010)
C API: Fix #49 (compilation under VS2010)

kornefalk/ocilib2017,vrogier/ocilib,ljx0305/ocilib,ljx0305/ocilib,vrogier/ocilib,ljx0305/ocilib,vrogier/ocilib,kornefalk/ocilib2017,vrogier/ocilib,kornefalk/ocilib2017