how to create a patch for configure?

[Joshua Root]

On 2018-4-15 11:11 , macports at parvis.nl wrote:
> I made a patch resulting in
> 
> pango configure.ac:221
> ----------------------
>     if $have_fontconfig ; then
>       pango_save_libs=$LIBS
>       LIBS="$LIBS $FONTCONFIG_LIBS"
> ->    # AC_CHECK_FUNCS(FcWeightFromOpenTypeDouble)
> ->    cat >>confdefs.h <<_ACEOF
> ->  #define HAVE_FCWEIGHTFROMOPENTYPEDOUBLE 1
> ->  _ACEOF
>       LIBS=$pango_save_libs
>     fi
> 
> but Autoconf didn't run so configure was not updated so nothing changes.
> 
> Q1: if the patch result correct?
> Q2: How should I do this in Portfile ?

To update configure you have to set use_autoconf or use_autoreconf.
However you may be able to not patch anything and pass
ac_cv_func_FcWeightFromOpenTypeDouble=yes to configure on the command
line or in the environment. Or, update fontconfig to 2.13.0 and bypass
the problem.

- Josh