warning cleanup: GNU C++ initializer warnings.

This is the eight and final round of an effort to enable
GCC's -Wextra option. The C++ compiler, with -Wextra,
doesn't like C's universal struct initializer { 0 },
individually complaining about all the remaining members
not being initialized. What works in C++ is the { }
initializer. Conditional definition to the rescue.

* lib.h (all_zero_init): New macro which expands to
{ } under C++, and { 0 } under C.

* lib.c (make_time_impl, epoch_tm, time_string_meth,
time_parse_meth): Use all_zero_init.

* parser.c (prime_parser): Likewise.

* socket.c (sock_mark_connected): Likewise.

* sysif.c (fcntl_wrap): Likewise.

* termios.c (encode_speeds, decode_speeds): Likewise.

* configure (diag_flags): Add -Wextra.

1 files changed, 2 insertions, 2 deletions

diff --git a/termios.c b/termios.c
index 6179f2b5..5d7b26b0 100644
--- a/termios.c
+++ b/termios.c
@@ -337,7 +337,7 @@ static val tcflow_wrap(val action, val stream)
 
 static val encode_speeds(val termios)
 {
-  struct termios tio = { 0 };
+  struct termios tio = all_zero_init;
 
   tio.c_iflag = c_num(slot(termios, iflag_s));
   tio.c_cflag = c_num(slot(termios, cflag_s));
@@ -351,7 +351,7 @@ static val encode_speeds(val termios)
 
 static val decode_speeds(val termios)
 {
-  struct termios tio = { 0 };
+  struct termios tio = all_zero_init;
 
   tio.c_cflag = c_num(slot(termios, cflag_s));
   tio.c_iflag = c_num(slot(termios, iflag_s));