https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108568
--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:815e5740162d2d0b7b54031f72c201065016d58c commit r13-5461-g815e5740162d2d0b7b54031f72c201065016d58c Author: Jakub Jelinek <ja...@redhat.com> Date: Fri Jan 27 20:11:20 2023 +0100 libstdc++: Fix up FAIL in 17_intro/names.cc on glibc < 2.19 [PR108568] On gcc112 which has glibc 2.17 I've noticed FAIL: 17_intro/names.cc (test for excess errors) FAIL: experimental/names.cc (test for excess errors) These are because glibc < 2.19 used __unused as field member of various structs, including mcontext_t in sys/ucontext.h on ppc64le. This was changed in glibc with https://gcc.gnu.org/pipermail/libc-alpha/2013-November/045766.html names.cc even has #ifdef __GLIBC_PREREQ #if ! __GLIBC_PREREQ(2, 19) // Glibc defines this prior to 2.19 #undef __unused #endif #endif for it, but it doesn't work. The reason is that __GLIBC_PREREQ is defined in <features.h> but nothing included that header before this spot (it is included later from bits/stdc++.h). The following patch on Linux/Hurd conditionally includes features.h to get the needed macros before deciding if __unused should be undefined or not. If needed, I could use __GLIBC_PREREQ then but would need to check if it is defined and between 1996 and 1999 it wasn't. 2023-01-27 Jakub Jelinek <ja...@redhat.com> PR libstdc++/108568 * testsuite/17_intro/names.cc (__unused): For linux or GNU hurd include features.h if present and then check __GLIBC__ and __GLIBC_MINOR__ macros for glibc prior to 2.19, instead of testing __GLIBC_PREREQ which isn't defined yet.
