Use the Microsoft _vscprintf() function which was just missing
a prototype in earlier versions of MinGW's stdio.h header.

Tell the user if they try this.  They'll get an error from
asInit() later, but it gets lost easily in other noise.

* Use clang and clang++
* Build for x86_64 only

Don't add extraneous characters when SHRLIB_VERSION or GNU_TARGET
are empty.  The addprefix or addsuffix functions only include the
prefix/suffix part if the list argument is not empty.

This fixes issues naming libCap5.so at build-time.

Also warns about some bad characters in record names, but only
the ones that are known to cause known bad behaviour.

All other host architectures have this setting commented out in
their host-specific CONFIG_SITE.<host>.Common files, so the user
doesn't get confused.

All are now robust against overflow, NAN or negative argument.
Passing seconds=0 calls the OS scheduler, offering to yield.
Passing seconds>0 delays at least the requested time, up to a
limit which usually depends on the OS tick rate.

Reported by Hinko Kocevar.

All site-specific values should be set in CONFIG_SITE files.

Fixes lp:999167

The callbackRequest() routine can be called from an ISR,
so use epicsInterruptContextMessage() to print errors.

This makes the uninitilized value not the Run state.

Using COMMENT the ECHO command drops the whole line under -s,
whereas using NOP (':') only drops up to the next ';' terminator.

Delete spurious global symbols
Remove unnecessary casts
Fix (c) headers
Added missing #include guard
Remove unnecessary #includes
Prettified.

Now works properly on Darwin where the version number comes
before the .dylib extension.  This also makes Windows-specific
conditional tests fully generic.

From Dirk Zimoch.

Update record timestamp before calling db_post_events()

This is really a workaround for a Win32/MinGW bug in sscanf, which
will only set the %n argument for the format "%u %n" when there is
a space following the unsigned number.

This changes the IOC's behavior very slightly.

Report throw from first call to epicsTime::getCurrent().
Reorganized test order so a bad time provider doesn't stop
all tests from being run.  Also cleaned up a few extraneous
variables.

Some of the isnan(Inf) tests were failing on mingw.
This change doesn't fix them, it adds related examples.

Makes it easy for users to select which compiler to use.

Apparently this hasn't been needed for quite a while.

This test fails if the cwd is not writable, but on vxWorks the
fault appears at the fclose() not the fopen() line. The code
now detects this and tells the user what's probably wrong.

Windows stack sizes were the same as vxWorks - tiny.
The stack sizes are now multiples of sizeof(void*).
On 32-bit systems they give 256KB, 512KB and 1MB;
64-bit systems get twice those numbers.

Fixes lp:903448