Between Texinfo 6.7 and 6.8, a change took place where CPPFLAGS is no longer populated in the file tp/Texinfo/XS/Makefile (created from tp/Texinfo/XS/Makefile.in). However, it is populated a few folders up in tp/Makefile (Created from tp/Makefile.in).
When using `--with-libintl-prefix[=DIR]`, this populates CPPFLAGS. Before 6.8, the value for CPPFLAGS was used in tp/Texinfo/XS. It no longer is, and that is probably because the build system is supposed to be self-contained and not inherit variables from the top-level build system. However, presumably `--with-libintl-prefix` is set because otherwise libintl.h will be missing otherwise. Now when building the XS folder contents, the api.c file is missing a needed include of libintl.h on all machines that don’t come preinstalled with libintl.h in the /usr/include (like Macs). Best regards, Paul Kuberry
