gnulib warnings during compilation

[Rik]

12/1/14

I'm getting 3 warnings when I compile with -O0, which I do not get when I
compile with -O2.  They are:

--- Warning List ---
system/oct-time.cc:238:38: warning: call to 'localtime' declared with
attribute warning: The symbol ::localtime refers to the system function.
Use gnulib::localtime instead. [enabled by default]
system/oct-time.cc:248:35: warning: call to 'gmtime' declared with
attribute warning: The symbol ::gmtime refers to the system function. Use
gnulib::gmtime instead. [enabled by default]
corefcn/load-save.cc:1204:28: warning: call to 'gmtime' declared with
attribute warning: The symbol ::gmtime refers to the system function. Use
gnulib::gmtime instead. [enabled by default]
--- End Warning List ---

It is true that the code isn't decorated with the gnulib:: prefix so this
is calling the system function.  Is that alright?  Currently configure does
not check that these functions are available using AC_CHECK_FUNC so I
suppose it is possible that someone has a libc which doesn't implement
them.  One approach is to do nothing.  A second would be to add
AC_CHECK_FUNC calls for the gmtime and localtime functions.  A third would
be to add gmtime and localtime to the gnulib bootstrap.conf file and then
decorate these three instances with gnulib::.  Does anyone like one of
these solutions more than another?

Cheers,
Rik