Building any application with gcc 7.1.1 fails with the following error:
```
~/RIOT % make -C examples/hello-world
make: Entering directory 'RIOT/examples/hello-world'
Building application "hello-world" for "native" with MCU "native".
"make" -C RIOT/boards/native
"make" -C RIOT/boards/native/drivers
"make" -C RIOT/core
"make" -C RIOT/cpu/native
RIOT/cpu/native/startup.c: In function ‘startup’:
RIOT/cpu/native/startup.c:292:17: error: this statement may fall through [-Werror=implicit-fallthrough=]
usage_exit(EXIT_SUCCESS);
^~~~~~~~~~~~~~~~~~~~~~~~
RIOT/cpu/native/startup.c:293:13: note: here
case 'i':
^~~~
cc1: all warnings being treated as errors
make[2]: *** [RIOT/Makefile.base:81: RIOT/examples/hello-world/bin/native/cpu/startup.o] Error 1
make[1]: *** [RIOT/Makefile.base:20: ALL--RIOT/cpu/native] Error 2
make: *** [RIOT/examples/hello-world/../../Makefile.include:297: all] Error 2
make: Leaving directory 'RIOT/examples/hello-world'
```
```
% gcc --version
gcc (GCC) 7.1.1 20170528
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
```
fixed by adding a `break` statement after `usage_exit()`
uart0 functionality is removed by #3164. This patch implements periph/uart,
rather than deprecated uart0, using /dev/tty.
To use with netdev2_tap simultaneously, this patch adds asynchronus read system
and modifies netdev2_tap to use it.
A TTY device is specified on command line with -c (COM) option, since -t was
used by the old implementation.
This patch also implements empty GPIO driver needed by the xbee driver.
The hwtimer_wait test was tortured with the
following script which ran several hours.
----
make clean all-debug
while :
do
date
./bin/native/hwtimer_wait.elf > log &
pid=$!
sleep 20
success=$(cat log|grep success)
if [ "$success" != "success" ]
then
date
echo "BUG"
exit
fi
kill $pid
done
----
Closes#715.
Per default random data is read from `/dev/random` now.
If specified (e.g. `-s 4711`), data is generated by calls to POSIX
random function like before. The POSIX random API is initialize with
the given seed (`srandom(4711);` in this example).
When using socket stdio, add option to replay what has been written to
stdout while not connected (`-r`).
The implementation is to simply use the existing log file (which is
implicitly created when the option is used), and read from it until
EOF upon reconnect.
closes#476
