v6_0_20170415 build fail with termcap and widec enabled

[Chi-Hsuan Yen]

Hello ncurses experts,

I build ncurses with ./configure --enable-widec --enable-termcap. It
always ran fine until yesterday. With version v6_0_20170415 it fails
with the following error:

gcc -DHAVE_CONFIG_H -I../ncurses -I. -I../include  -D_GNU_SOURCE
-D_DEFAULT_SOURCE -DNDEBUG -O2 --param max-inline-insns-single=1200 -c
../ncurses/./tinfo/read_termcap.c -o ../objects/read_termcap.o
../ncurses/./tinfo/read_termcap.c:959:1: error: conflicting types for
‘_nc_read_termcap_entry’
 _nc_read_termcap_entry(const char *const tn, TERMTYPE *const tp)
 ^~~~~~~~~~~~~~~~~~~~~~
In file included from ../ncurses/./tinfo/read_termcap.c:53:0:
../ncurses/curses.priv.h:2081:28: note: previous declaration of
‘_nc_read_termcap_entry’ was here
 extern NCURSES_EXPORT(int) _nc_read_termcap_entry (const char *const,
TERMTYPE2 *const);
                            ^~~~~~~~~~~~~~~~~~~~~~
../ncurses/./tinfo/read_termcap.c: In function ‘_nc_read_termcap_entry’:
../ncurses/./tinfo/read_termcap.c:1157:7: error: incompatible types
when assigning to type ‘TERMTYPE {aka struct termtype}’ from type
‘TERMTYPE2 {aka struct termtype2}’
   *tp = ep->tterm;
       ^

I roll back to v6_0_20170408 and the build is working again. Seems
it's a regression? Thanks for any input.

Environment: Arch Linux x86_64 with GCC 6.3.1

Best,

Yen Chi-Hsuan