Newlib modified for the FreeChainXenon project
cf86601d98
svfwscanf replaces getwc and ungetwc_r. The comments in the code talk about avoiding file operations, but they also need to bypass the mbtowc calls as svfwscanf operates on wchar_t, not multibyte data, which is a more important reason here; they would not work correctly otherwise. The ungetwc replacement has code which uses the 3 byte FILE _ubuf field, but if wchar_t is 32-bits, this field is not large enough to hold even one wchar_t value. Building in this mode generates warnings about array overflow: In file included from ../../newlib/libc/stdio/svfiwscanf.c:35: ../../newlib/libc/stdio/vfwscanf.c: In function '_sungetwc_r.isra': ../../newlib/libc/stdio/vfwscanf.c:316:12: warning: array subscript 4294967295 is above array bounds of 'unsigned char[3]' [-Warray-bounds] 316 | fp->_p = &fp->_ubuf[sizeof (fp->_ubuf) - sizeof (wchar_t)]; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from ../../newlib/libc/stdio/stdio.h:46, from ../../newlib/libc/stdio/vfwscanf.c:82, from ../../newlib/libc/stdio/svfiwscanf.c:35: ../../newlib/libc/include/sys/reent.h:216:17: note: while referencing '_ubuf' 216 | unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */ | ^~~~~ However, the vfwscanf code *never* ungets data before the start of the scanning operation, and *always* ungets data which matches the input at that point, so the code always hits the block which backs up over the input data and never hits the block which uses the _ubuf field. In addition, the svfwscanf code will always start with the unget buffer empty, so the ungetwc replacement never needs to support an unget buffer at all. Simplify the code by removing support for everything other than backing up over the input data, leaving the check to make sure it doesn't get underflowed in case the vfscanf code has a bug in it. Signed-off-by: Keith Packard <keithp@keithp.com> |
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| libgloss | ||
| newlib | ||
| texinfo | ||
| winsup | ||
| .appveyor.yml | ||
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| ChangeLog | ||
| compile | ||
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| configure | ||
| configure.ac | ||
| COPYING | ||
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| MAINTAINERS | ||
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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.