also search for the library directory (init.tcl, encodings, etc) relative to the build directory associated with the source checkout.
merge 8.4
360894 Threads inherit floating point config from their creator thread
360894 Threads inherit floating point config from their creator thread.
360894 Threads inherit floating point config from their creator thread
merge trunk
Workaround for mingw versions which don't provide _fpcontrol in float.h
Workaround for mingw versions which don't provide _fpcontrol in float.h
Workaround for mingw versions which don't provide _fpcontrol in float.h
merge trunk
	* unix/tclUnixFCmd.c (TclUnixOpenTemporaryFile): [Bug 2933003]: Factor
	out all the code to do temporary file creation so that it is possible
	to make it correct in one place. Allow overriding of the back-stop
	default temporary file location at compile time by setting the
	TCL_TEMPORARY_FILE_DIRECTORY #def to a string containing the directory
	name (defaults to "/tmp" as that is the most common default).
Backport from Tcl 8.6.
	* unix/tclUnixPipe.c (DefaultTempDir): [Bug 2933003]: Allow overriding
	of the back-stop default temporary file location at compile time by
	setting the TCL_TEMPORARY_FILE_DIRECTORY #def to a string containing
	the directory name (defaults to "/tmp" as that is the most common
	default).
	* unix/tclUnixPipe.c (DefaultTempDir): [Bug 2933003]: Allow overriding
	of the back-stop default temporary file location at compile time by
	setting the TCL_TEMPORARY_FILE_DIRECTORY #def to a string containing
	the directory name (defaults to "/tmp" as that is the most common
	default).
merge mark
Fix botched patch
merge trunk
3587242	Missing Tcl_MutexUnlock() call made [testasync create] block.
IMPLEMENTATION OF TIP#416: New Options for 'load': -global and -lazy
unbreak trunk; fix some warnings
merge trunk: