Make getenv thread-safe in more cases (RHEL-42410)

Minor update to getrandom vDSO handshake

CVE-2024-12455: Incorrect getrandom return value on ppc64le

Sync with upstream branch release/2.39/master,
elf: Change ldconfig auxcache magic number (bug 32231)
Make tst-strtod-underflow type-generic
Add crt1-2.0.o for glibc 2.0 compatibility tests
Add tests of more strtod special cases
Add more tests of strtod end pointer
Make tst-strtod2 and tst-strtod5 type-generic
powerpc64le: Build new strtod tests with long double ABI flags (bug 32145)
Do not set errno for overflowing NaN payload in strtod/nan (bug 32045)
Improve NaN payload testing
Make __strtod_internal tests type-generic
Fix strtod subnormal rounding (bug 30220)
More thoroughly test underflow / errno in tst-strtod-round
Test errno setting on strtod overflow in tst-strtod-round
Add tests of fread
stdio-common: Add new test for fdopen
libio: Attempt wide backup free only for non-legacy code
debug: Fix read error handling in pcprofiledump
elf: Fix tst-dlopen-tlsreinit1.out test dependency
elf: Avoid re-initializing already allocated TLS in dlopen (bug 31717)
elf: Clarify and invert second argument of _dl_allocate_tls_init
elf: Support recursive use of dynamic TLS in interposed malloc
nptl: Use <support/check.h> facilities in tst-setuid3
posix: Use <support/check.h> facilities in tst-truncate and tst-truncate64
ungetc: Fix backup buffer leak on program exit [BZ #27821]
ungetc: Fix uninitialized read when putting into unused streams [BZ #27821]
Make tst-ungetc use libsupport
stdio-common: Add test for vfscanf with matches longer than INT_MAX [BZ #27650]
support: Add FAIL test failure helper
string: strerror, strsignal cannot use buffer after dlmopen (bug 32026)
Define __libc_initial for the static libc
x86: Fix bug in strchrnul-evex512 [BZ #32078]
Adjust check-local-headers test for libaudit 4.0
x32/cet: Support shadow stack during startup for Linux 6.10
x86-64: Remove sysdeps/x86_64/x32/dl-machine.h
support: Add options list terminator to the test driver
manual/stdio: Further clarify putc, putwc, getc, and getwc
Fix name space violation in fortify wrappers (bug 32052)
resolv: Fix tst-resolv-short-response for older GCC (bug 32042)
Add mremap tests
mremap: Update manual entry
linux: Update the mremap C implementation [BZ #31968]
Enhanced test coverage for strncmp, wcsncmp
Enhance test coverage for strnlen, wcsnlen

Add support for getrandom vDSO (RHEL-12867)

Eliminate glibc-headers and related packages

Complete Features/UsrMove (aka UsrMerge, MoveToUsr) transition (#1063607)

Rework filelist construction

Switch to the upstream way of building xtests

Bump release for October 2024 mass rebuild:
64018

Ensure that xtests can be built (RHEL-59494)

Support clearing options in /etc/resolv.conf, RES_OPTIONS with a - prefix
Introduce the strict-error/RES_STRICTERR stub resolver option (RHEL-18039)

Sync with upstream branch release/2.39/master,
manual: make setrlimit() description less ambiguous
manual/stdio: Clarify putc and putwc
malloc: add multi-threaded tests for aligned_alloc/calloc/malloc
malloc: avoid global locks in tst-aligned_alloc-lib.c
resolv: Track single-request fallback via _res._flags (bug 31476)
resolv: Do not wait for non-existing second DNS response after error (bug 30081)
resolv: Allow short error responses to match any query (bug 31890)
elf: Fix localplt.awk for DT_RELR-enabled builds (BZ 31978)
Fix usage of _STACK_GROWS_DOWN and _STACK_GROWS_UP defines [BZ 31989]
Linux: Make __rseq_size useful for feature detection (bug 31965)
elf: Make dl-rseq-symbols Linux only
s390x: Fix segfault in wcsncmp [BZ #31934]
stdlib: fix arc4random fallback to /dev/urandom (BZ 31612)
math: Provide missing math symbols on libc.a (BZ 31781)
math: Fix isnanf128 static build (BZ 31774)
math: Fix i386 and m68k exp10 on static build (BZ 31775)
math: Fix i386 and m68k fmod/fmodf on static build (BZ 31488)
posix: Fix pidfd_spawn/pidfd_spawnp leak if execve fails (BZ 31695)

Support --without testsuite builds without perl installed (#2292195)

Add Conflicts:/Obsoletes: for glibc32 to glibc.i686

ppc64le: Build early startup code with -mcpu=power8