mirror of
git://sourceware.org/git/newlib-cygwin.git
synced 2025-01-18 12:29:32 +08:00
668a4c8722
In Newlib, the stdio streams are defined to thread-specific pointers _reent::_stdin, _reent::_stdout and _reent::_stderr. In case _REENT_SMALL is not defined, then these pointers are initialized via _REENT_INIT_PTR() or _REENT_INIT_PTR_ZEROED() to thread-specific FILE objects provided via _reent::__sf[3]. There are two problems with this (at least in case of RTEMS). (1) The thread-specific FILE objects are closed by _reclaim_reent(). This leads to problems with language run-time libraries that provide wrappers to the C/POSIX stdio streams (e.g. C++ and Ada), since they use the thread-specific FILE objects of the initialization thread. In case the initialization thread is deleted, then they use freed memory. (2) Since thread-specific FILE objects are used with a common output device via file descriptors 0, 1 and 2, the locking at FILE object level cannot ensure atomicity of the output, e.g. a call to printf(). Introduce a new Newlib configuration option _REENT_GLOBAL_STDIO_STREAMS to enable the use of global stdio FILE objects. As a side-effect this reduces the size of struct _reent by more than 50%. The _REENT_GLOBAL_STDIO_STREAMS should not be used without _STDIO_CLOSE_PER_REENT_STD_STREAMS. Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.