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The lseek consolidation broke lseek64 for MIPS n32, so resulting in io/test-lfs failing with an incorrect return from ftello64. This configuration uses the lseek syscall with a 64-bit return value; as the C syscall macros return long, they cannot be used in this case and so an assembly implementation is needed; accordingly, this patch adds lseek64 back to syscalls.list for this configuration. lseek was also broken, truncating the result without checking for overflow. lseek however was already broken before the consolidation; it aliased lseek64 so would return an out-of-range value, resulting in architecturally undefined behavior in the caller if it tried to use a non-sign-extended value with a 32-bit instruction. This patch adds a custom lseek implementation in C for n32, which calls __lseek64 to get the 64-bit value then checks for overflow. Because the prior lseek breakage did not show in test results, and the lseek64 breakage showed only indirectly through tests of ftello64, test coverage was clearly inadequate. This patch extends io/test-lfs.c to test the lseek64 return value (at a point where it has already seeked over 2GB into a file), and then to test the lseek return value (with the latter's expectations depending on whether off_t is smaller than off64_t). Tested for mips64 n32. Also tested test-lfs for x86_64 and x86, where as expected it passes. [BZ #21019] * sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list (lseek64): New syscall entry. * sysdeps/unix/sysv/linux/mips/mips64/n32/lseek.c: New file. * io/test-lfs.c (do_test): Test offset returned from lseek64 and lseek.
This directory contains the sources of the GNU C Library. See the file "version.h" for what release version you have. The GNU C Library is the standard system C library for all GNU systems, and is an important part of what makes up a GNU system. It provides the system API for all programs written in C and C-compatible languages such as C++ and Objective C; the runtime facilities of other programming languages use the C library to access the underlying operating system. In GNU/Linux systems, the C library works with the Linux kernel to implement the operating system behavior seen by user applications. In GNU/Hurd systems, it works with a microkernel and Hurd servers. The GNU C Library implements much of the POSIX.1 functionality in the GNU/Hurd system, using configurations i[4567]86-*-gnu. The current GNU/Hurd support requires out-of-tree patches that will eventually be incorporated into an official GNU C Library release. When working with Linux kernels, this version of the GNU C Library requires Linux kernel version 3.2 or later on all architectures except i[4567]86 and x86_64, where Linux kernel version 2.6.32 or later suffices. Also note that the shared version of the libgcc_s library must be installed for the pthread library to work correctly. The GNU C Library supports these configurations for using Linux kernels: aarch64*-*-linux-gnu alpha*-*-linux-gnu arm-*-linux-gnueabi hppa-*-linux-gnu Not currently functional without patches. i[4567]86-*-linux-gnu x86_64-*-linux-gnu Can build either x86_64 or x32 ia64-*-linux-gnu m68k-*-linux-gnu microblaze*-*-linux-gnu mips-*-linux-gnu mips64-*-linux-gnu powerpc-*-linux-gnu Hardware or software floating point, BE only. powerpc64*-*-linux-gnu Big-endian and little-endian. s390-*-linux-gnu s390x-*-linux-gnu sh[34]-*-linux-gnu sparc*-*-linux-gnu sparc64*-*-linux-gnu tilegx-*-linux-gnu tilepro-*-linux-gnu If you are interested in doing a port, please contact the glibc maintainers; see http://www.gnu.org/software/libc/ for more information. See the file INSTALL to find out how to configure, build, and install the GNU C Library. You might also consider reading the WWW pages for the C library at http://www.gnu.org/software/libc/. The GNU C Library is (almost) completely documented by the Texinfo manual found in the `manual/' subdirectory. The manual is still being updated and contains some known errors and omissions; we regret that we do not have the resources to work on the manual as much as we would like. For corrections to the manual, please file a bug in the `manual' component, following the bug-reporting instructions below. Please be sure to check the manual in the current development sources to see if your problem has already been corrected. Please see http://www.gnu.org/software/libc/bugs.html for bug reporting information. We are now using the Bugzilla system to track all bug reports. This web page gives detailed information on how to report bugs properly. The GNU C Library is free software. See the file COPYING.LIB for copying conditions, and LICENSES for notices about a few contributions that require these additional notices to be distributed. License copyright years may be listed using range notation, e.g., 1996-2015, indicating that every year in the range, inclusive, is a copyrightable year that would otherwise be listed individually.