changed from [USE_TLS && HAVE___THREAD].
* sysdeps/i386/dl-machine.h (elf_machine_type_class, elf_machine_rel):
Disable TLS relocs if [RTLD_BOOTSTRAP && !USE___THREAD].
* sysdeps/x86_64/dl-machine.h
(elf_machine_type_class, elf_machine_rela): Likewise.
* sysdeps/sh/dl-machine.h (elf_machine_type_class, elf_machine_rela):
Likewise.
* include/link.h (struct link_map): Remove member l_tls_tp_initialized.
* elf/rtld.c (_dl_start_final, dl_main): Don't use it.
(_dl_start): Conditionalize PT_TLS check on [USE___THREAD].
* sysdeps/i386/dl-tls.h (__TLS_GET_ADDR): Use ___tls_get_addr_internal
instead of ___tls_get_addr.
(___tls_get_addr_internal): Add attribute_hidden to decl.
* sysdeps/generic/ldsodefs.h (struct rtld_global): New variable
_dl_error_catch_tsd.
* elf/rtld.c (startup_error_tsd): New function.
(dl_main): Point _dl_error_catch_tsd at that.
* elf/dl-error.c: Don't use libc-tsd.h for DL_ERROR,
use new function pointer instead.
* elf/dl-tsd.c: New file.
* elf/Makefile (routines): Add it.
2002-10-07 Roland McGrath <roland@redhat.com>
* elf/dl-misc.c (_dl_debug_vdprintf): Use INTERNAL_SYSCALL macro for
writev if it's available. Otherwise if [RTLD_PRIVATE_ERRNO] then
take _dl_load_lock around calling __writev.
* sysdeps/unix/sysv/linux/i386/sysdep.h (INTERNAL_SYSCALL): New macro.
(INLINE_SYSCALL): Use that.
* sysdeps/generic/dl-sysdep.h: New file.
* sysdeps/mach/hurd/dl-sysdep.h: New file.
* sysdeps/generic/ldsodefs.h: Include <dl-sysdep.h>.
* include/errno.h [IS_IN_rtld]: Include <dl-sysdep.h> to define ...
[RTLD_PRIVATE_ERRNO]: Use a hidden global variable for errno and
access it directly.
* elf/dl-minimal.c (__errno_location): Removed.
* sysdeps/unix/i386/sysdep.S (__syscall_errno) [RTLD_PRIVATE_ERRNO]:
Use GOTOFF access for errno.
* sysdeps/unix/sysv/linux/i386/sysdep.h
[RTLD_PRIVATE_ERRNO] (SYSCALL_ERROR_HANDLER): Likewise.
* sysdeps/unix/x86_64/sysdep.S (__syscall_errno) [RTLD_PRIVATE_ERRNO]:
Use PC-relative access for errno.
* sysdeps/unix/sysv/linux/x86_64/sysdep.h
[RTLD_PRIVATE_ERRNO] (SYSCALL_ERROR_HANDLER): Likewise.
* include/tls.h: New file.
(USE___THREAD): New macro.
Define to 1 under [USE_TLS && HAVE___THREAD] and only when compiling
libc or libpthread.
* sysdeps/unix/sysv/linux/i386/sysdep.h [USE___THREAD]: Conditional
changed from [USE_TLS && HAVE___THREAD].
* sysdeps/unix/sysv/linux/x86_64/sysdep.h: Likewise.
* sysdeps/unix/i386/sysdep.S: Likewise.
* sysdeps/unix/x86_64/sysdep.S: Likewise.
* include/errno.h: Likewise.
* include/netdb.h: Likewise.
* include/resolv.h: Likewise.
* sysdeps/generic/errno.c: New file.
* csu/Makefile (aux): New variable, list errno.
* sysdeps/unix/sysv/linux/i386/sysdep.S (errno, _errno): Remove defns.
* sysdeps/unix/sysv/linux/m68k/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/arm/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/cris/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/hppa/sysdep.c: Likewise.
* sysdeps/unix/sysv/linux/ia64/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/powerpc/sysdep.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sysdep.S: Likewise.
* sysdeps/unix/sysv/linux/sh/sysdep.S: Likewise.
* sysdeps/unix/alpha/sysdep.S: Likewise.
* sysdeps/generic/start.c: Likewise.
* sysdeps/unix/start.c: Likewise.
* sysdeps/unix/arm/start.c: Likewise.
* sysdeps/unix/bsd/ultrix4/mips/start.S: Likewise.
* sysdeps/unix/sparc/start.c: Likewise.
* sysdeps/unix/sysv/irix4/start.c: Likewise.
* sysdeps/unix/sysv/linux/mips/sysdep.S: File removed.
* manual/search.texi (Tree Search Function, Hash Search Function):
Mention search.h clearly.
2002-10-05 Roland McGrath <roland@redhat.com>
* elf/dl-fxstat64.c: File removed.
* elf/dl-xstat64.c: File removed.
* elf/Makefile (rtld-routines): Remove them.
* sysdeps/unix/sysv/linux/xstat64.c: Remove RTLD_STAT64 conditionals.
Instead, use strong_alias instead of versioned_symbol in the
!SHLIB_COMPAT case.
* sysdeps/unix/sysv/linux/fxstat64.c: Likewise.
* sysdeps/unix/sysv/linux/lxstat64.c: Likewise.
* include/shlib-compat.h
(SHLIB_COMPAT): Require that IS_IN_##lib be defined nonzero.
[! NOT_IN_libc] (IS_IN_libc): Define it.
* cppflags-iterator.mk (CPPFLAGS-$(cpp-src)): Use -Dx=1 not just -Dx.
* elf/Makefile (CPPFLAGS-.os): Likewise.
* sunrpc/rpc_main.c (main): Don't declare with noreturn attribute.
Return the status instead of calling exit.
* Makeconfig (CFLAGS): Prepend -std=gnu99.
* Makerules (+make-deps): Use $(CFLAGS) only for .c sources.
Remove superfluous rm command, whose @ plus make bugs hid
all these commands from the make output.
* include/stubs-prologue.h: New file. Give #error under #ifdef _LIBC.
* Makefile ($(inst_includedir)/gnu/stubs.h): Depend on it.
Use that file's contents instead of literal echo's for the prologue.
* include/features.h: Include <gnu/stubs.h> unconditionally.
* include/gnu/stubs.h: New file.
2002-09-30 Roland McGrath <roland@redhat.com>
* elf/rtld-Rules: New file.
* elf/Makefile ($(objpfx)librtld.map, $(objpfx)librtld.mk,
$(objpfx)rtld-libc.a): New targets.
(generated): Add them.
(reloc-link): Remove -o $@ from the variable.
($(objpfx)dl-allobjs.os): Add -o $@ after $(reloc-link).
(distribute): Add rtld-Rules.
(CPPFLAGS-.os): Define this instead of CFLAGS-.os.
* Makerules ($(+sysdir_pfx)sysd-rules): Emit rules for rtld-% targets.
(common-mostlyclean, common-clean): Clean up rtld-* files.
* sysdeps/unix/make-syscalls.sh: Add rtld-*.os target name to rules.
2002-08-27 Ulrich Drepper <drepper@redhat.com>
* sysdeps/arm/Dist: Add bits/link.h.
* sunrpc/Makefile: Distribute thrsvc.
* stdio-common/Makefile: Remove more left-overs from old stdio.
* include/linewrap.h: Removed.
* libio/bug-mmap-fflush.c: Rewrite to not touch source directory.
* intl/Makefile (distribute): Add plural-eval.c.
* stdio-common/Makefile (headers): Remove bits/stdio_lim.h. This
file isn't distributed. Add special rules to install bits/stdio_lim.h.
* Make-dist: Remove traces of old stdio.
* Makeconfig: Likewise.
* locale/Makefile (localedef-aux): New variable. Only md5
assigned to it. These files are not ddistributed in this directory.
* sysdeps/unix/sysv/linux/s390/Dist: Add sys/procfs.h.
* sysdeps/unix/sysv/linux/s390/s390-64/Dist: Remove sys/procfs.h.
* sysdeps/unix/sysv/linux/s390/s390-32/Dist: Likewise.
* sysdeps/unix/sysv/linux/Dist: Remove sys/sendfile.h.
* Makeconfig (%.v.i, %.v): New implicit rules.
(preprocess-versions): Variable removed.
($(common-objpfx)shlib-versions.v.i): New target giving just the
shlib-versions input files as dependencies.
($(common-objpfx)soversions.i): Depend on that instead of the input
files. Use it as input instead of using a pipeline.
(postclean-generated): Append soversions.i, shlib-versions.v, and
shlib-versions.v.i here.
* Makerules ($(common-objpfx)Versions.def.v.i): New target giving just
the Versions.def input files as dependencies.
($(common-objpfx)Versions.v.i): Likewise for Versions files.
($(common-objpfx)Versions.all): Depend on that instead of the input
files. Use it as input instead of using a pipeline.
($(common-objpfx)sysd-versions): Likewise with Versions.v.i.
(postclean-generated): Append those .v and .v.i files here.
2001-08-28 H.J. Lu <hjl@gnu.org>
* Makeconfig (combreloc-LDFLAGS): New variable.
Add it to LDFALGS.so, LDFLAGS-rtld, and +link.
* config.make.in (have-z-combreloc): New variable.
* configure.in: Substitute libc_cv_z_combreloc.
* iconv/strtab.c (searchstring): Use correct length for comparison.
2001-07-06 Paul Eggert <eggert@twinsun.com>
* manual/argp.texi: Remove ignored LGPL copyright notice; it's
not appropriate for documentation anyway.
* manual/libc-texinfo.sh: "Library General Public License" ->
"Lesser General Public License".
2001-07-06 Andreas Jaeger <aj@suse.de>
* All files under GPL/LGPL version 2: Place under LGPL version
2.1.
2001-05-09 Michael Keezer <mkeezer@redhat.com>
* Makeconfig: Added AIX-ld support for DSO.
* Makerules: Likewise.
* dlfcn/Makefile (defaultmod1.so): Added libc_nonshared.
(defaultmod2.so): Likewise.
* debug/Makefile: Conditionalize use of elf/ld.so.
* iconvdata/Makefile: Moved LDFLAG rpath/soname info into Makeconfig.
* sysdeps/unix/sysv/aix/Makefile: Added dl-support.c and dl-error.c.
* sysdeps/unix/sysv/aix/Makefile: Made (f/g)rsave(0/1) &
(f/g)prrest(0/1) static only.
* sysdeps/unix/sysv/aix/gettimeofday.c: Removed #if 0.
* sysdeps/unix/sysv/aix/start.c: Define __dso_handle if not ELF but
shared.
* sysdeps/unix/sysv/aix/setitimer.c: New file.
* sysdeps/unix/sysv/aix/sleep.c: New file.
* sysdeps/unix/sysv/aix/usleep.c: New file.
* sysdeps/unix/sysv/aix/dl-addr.c: New file.
* sysdeps/unix/sysv/aix/dl-error.c: New file.
* sysdeps/unix/sysv/aix/dl-support.c: New file.
* sysdeps/unix/sysv/aix/powerpc/register-dump.h: New file.
(BODY for TO_LOOP): Keep track of Unicode 3.1 language tag. I f "ja",
prefer conversion to Japanese character sets. If "zh", prefer
conversion to GB2312. I f "ko", prefer conversion to KSC5601. Small
static pattern rule also that also covers
$(objpx)g$(static-start-installed-name).
[$(start-installed-name) != $(static-start-installed-name)]
(extra-objs, omit-deps, install-lib): Add
$(static-start-installed-name) and g$(static-start-installed-name).
* sysdeps/mach/hurd/i386/Makefile: Don't add crt0.o to those here;
just setting static-start-installed-name is now sufficient.
(extra-objs): Add static-start.o here.
(CFLAGS-initfini.s): Remove obsolete variable.
* sysdeps/mach/hurd/i386/Makeconfig: New file.
Define static-start-installed-name here.
* Makeconfig: Include existing $(full_config_sysdirs:=/Makeconfig).
* Make-dist (+sysdep-tsrcs): Look for Makeconfig files.
* Makerules ($(+sysdir_pfx)sysd-Makefile): Remove this target and
associated hair. Instead, just use $(wildcard ...) in the include.
* configure.in (critic_missing, aux_missing): Collect in these vars
the names of the missing programs, and include them in the error msgs.
* configure: Regenerated.
2000-12-09 Ulrich Drepper <drepper@redhat.com>
* Makeconfig (default_cflags): Make -O2 the default for stable
releases.
2000-12-08 H.J. Lu <hjl@gnu.org>
* sysdeps/ia64/fpu/s_isinfl.S: Renamed to ...
* sysdeps/ia64/fpu/s_isinf.S: This.
Add a .pred.rel.mutex note to avoid false report.
* sysdeps/ia64/fpu/s_isnanl.S: Renamed to ...
* sysdeps/ia64/fpu/s_isnan.S: This.
* sysdeps/ia64/fpu/s_fpclassify.S: New file.
* sysdeps/ia64/fpu/s_fpclassifyf.S: New file.
* sysdeps/ia64/fpu/s_fpclassifyl.S: New file.
* sysdeps/ia64/fpu/s_isinff.S: New file.
* sysdeps/ia64/fpu/s_isinfl.S: New file.
* sysdeps/ia64/fpu/s_isnanf.S: New file.
* sysdeps/ia64/fpu/s_isnanl.S: New file.
* sysdeps/ia64/fpu/s_finite.S: New file.
* sysdeps/ia64/fpu/s_finitef.S: New file.
* sysdeps/ia64/fpu/s_finitel.S: New file.
* sysdeps/ia64/fpu/s_signbit.S: New file.
* sysdeps/ia64/fpu/s_signbitf.S: New file.
* sysdeps/ia64/fpu/s_signbitl.S: New file.
* sysdeps/ia64/fpu/s_copysign.S: New file.
* sysdeps/ia64/fpu/s_copysignf.S: New file.
* sysdeps/ia64/fpu/s_copysignl.S: New file.
2000-11-28 Andreas Jaeger <aj@suse.de>
* sysdeps/unix/sysv/linux/getdents.c: Add _syscall_getdents64
declaration, adjust declaration of __syscall_getdents to match
kernel.
2000-11-20 Ulrich Drepper <drepper@redhat.com>
* configure.in: Add --enable-all-warnings.
* config.make.in (all-warnings): New variable.
* Makeconfig (+gccwarn): Define with many more warnings if
all-warnings is yes.
2000-11-15 Jakub Jelinek <jakub@redhat.com>
* dlfcn/default.c (main): Add test for dladdr of main returning
argv[0] in dli_fname field.
2000-11-15 Jakub Jelinek <jakub@redhat.com>
* Makeconfig (run-program-prefix): Move test-static test into the
variable.
* sysdeps/alpha/dl-machine.h (RTLD_START): Update _dl_argv.
* sysdeps/sparc/sparc32/dl-machine.h (RTLD_START): Likewise,
schedule instructions.
* sysdeps/sparc/sparc64/dl-machine.h (RTLD_START): Likewise,
schedule instructions, fix a bug in copying auxiliary data.
* manual/startup.texi (Program Arguments): Fix type of main's envp
parameter.
Reported by Ral Nez de Arenas Coronado <dervishd@linuxfreak.com>.
* Makeconfig: Ensures the soversions.mk part of Makefile gets
included before building gnu/lib-names.h
Patch by Maciej W. Rozycki <macro@ds2.pg.gda.pl>.
link-extra-libs-bounded): New variables.
(built-program-cmd): Omit $(run-program-prefix) for static BP tests.
* Makerules (do-tests-clean, common-mostlyclean): Remove BP test files.
* Rules (tests-bp.out): New variable.
(tests): Conditionally add BP tests.
(binaries-bounded): Add variable and associated rule.
* csu/Makefile [build-bounded] (extra-objs, install-lib):
Move conditional stuff after place where condition is defined.
2000-07-12 Bruno Haible <haible@clisp.cons.org>
* iconv/gconv_open.c (__gconv_open): Merge duplicated code.
2000-07-12 Bruno Haible <haible@clisp.cons.org>
* iconv/gconv_builtin.c (__gconv_get_builtin_trans): Initialize
__modname.
2000-07-12 Bruno Haible <haible@clisp.cons.org>
* iconv/gconv_open.c (__gconv_open): Initialize
result->__steps[cnt].__data.
2000-07-12 Mark Kettenis <kettenis@gnu.org>
* nss/getent.c (services_keys): Pass port number in network byte
order in call to getservbyport.
2000-07-11 Andreas Jaeger <aj@suse.de>
* stdlib/Makefile (test-canon-ARGS): Fix for building in the
source dir.
* intl/Makefile (do-gettext-test): Likewise.
* dirent/Makefile (opendir-tst1-ARGS): Likewise.
2000-07-11 Andreas Schwab <schwab@suse.de>
* Makeconfig (run-program-prefix): New rule.
(built-program-cmd): Use run-program-prefix.
* csu/Makefile (extra-objs, omit-deps, install-lib): Add
BP-flavored startup object.
($(objpfx)b$(start-installed-name)): New rule.
* include/libc-symbols.h (symbol_set_declare): Change type
of `__start_##set' and `__stop_##set' to pointer-to-function.
(symbol_set_declare): Change type of `set' to array of
pointer-to-function.
* include/set-hooks.h (RUN_HOOK): Change type of `ptr' to
pointer-to-function.
* Makeconfig: Add missing comment.
* csu/Makefile (extra-objs, omit-deps, install-lib): Add
BP-flavored startup object.
($(objpfx)b$(start-installed-name)): New rule.
* include/libc-symbols.h (symbol_set_declare): Change type
of `__start_##set' and `__stop_##set' to pointer-to-function.
(symbol_set_declare): Change type of `set' to array of
pointer-to-function.
* include/set-hooks.h (RUN_HOOK): Change type of `ptr' to
pointer-to-function.
2000-05-29 Jakub Jelinek <jakub@redhat.com>
* inet/rcmd.c (rresvport_af): Use correct port number.
2000-05-26 Andreas Schwab <schwab@suse.de>
* Makeconfig ($(common-objpfx)soversions.mk): Prepend `$lib=' to
entries in all-sonames.
($(common-objpfx)gnu/lib-names.h): Use it for the CPP symbol,
preserving the old name if different for compatibility.
2000-04-27 Ulrich Drepper <drepper@redhat.com>
* hesiod/nss_hesiod/hesiod-grp.c (_nss_hesiod_initgroups): Handle
overflows in conversion from ASCII.
2000-04-26 Jakub Jelinek <jakub@redhat.com>
* Makeconfig (full_config_sysdirs): Renamed from full-config-sysdirs.
* Makerules (full_config_sysdirs): Likewise.
* MakeTAGS (full_config_sysdirs): Likewise.
2000-04-26 Jakub Jelinek <jakub@redhat.com>
* .cvsignore: Remove linuxthreads.
* po/.cvsignore: Remove *.pot.
* posix/glob/.cvsignore: Removed.
* sysdeps/unix/bsd/osf/.cvsignore: Removed.
2000-04-25 Andreas Jaeger <aj@suse.de>
* conform/Makefile (distribute): Also distribute contents of
subdirectories.
* Makerules (no_deps): Remove abi-versions.h.
* nis/nis_print_group_entry.c: Include alloca.h for alloca prototype.
2000-04-25 Jakub Jelinek <jakub@redhat.com>
* sysdeps/sparc/sparc64/elf/Dist: Remove.
* sysdeps/sparc/sparc64/elf/crtbegin.S: Remove.
* sysdeps/sparc/sparc64/elf/crtbeginS.S: Remove.
* sysdeps/sparc/sparc64/elf/crtend.S: Remove.
* sysdeps/sparc/sparc64/elf/crtendS.S: Remove.
* sysdeps/sparc/sparc64/elf/Makefile: Don't build crtbegin/crtend
objects.
2000-04-25 Thorsten Kukuk <kukuk@suse.de>
* nscd/grpcache.c: Fix gr_name pointer [PR/1702].
2000-04-23 Bruno Haible <clisp.cons.org>
* intl/dcigettext.c: Define _GNU_SOURCE as early as possible.
* intl/l10nflist.c: Likewise.
2000-04-23 Bruno Haible <clisp.cons.org>
* intl/bindtextdom.c [!_LIBC]: Define __libc_rwlock_define,
__libc_rwlock_wrlock, __libc_rwlock_unlock as empty.
* intl/textdomain.c [!_LIBC]: Likewise.
* intl/dcigettext.c [!_LIBC]: Define __libc_rwlock_define_initialized,
__libc_rwlock_rdlock, __libc_rwlock_unlock as empty.
* intl/loadmsgcat.c (_nl_load_domain) [!_LIBC, !HAVE_ICONV]: Avoid
syntax error.
2000-04-23 Bruno Haible <clisp.cons.org>
* intl/dcigettext.c (_nl_find_msg): Do the plural treatment and
character set conversion also in the case the translation was found
after a hash collision or through binary search. Store the maximum
index together with the converted message. Use iconv() when available.
In case of out of memory during conversion, return the unconverted
translated string, not NULL.
* configure.in: If --disable-shared was given, don't set VERSIONING,
don't define DO_VERSIONING, and don't give scare warning for no
versioning.
* configure: Regenerated.
2000-04-02 Ulrich Drepper <drepper@redhat.com>
* elf/dl-fini.c (_dl_fini): Increment j counter after swapping in
element at this position.
* elf/Versions [ld.so] (GLIBC_2.2): Export _dl_load_lock.
* elf/link.h (struct link_map): Add l_reldepsmax, l_reldepsact, and
l_reldeps elements.
* elf/dl-lookup.c (add_dependency): New function.
(_dl_lookup_symbol): Use it whenever symbol was found in a global,
dynamically loaded object.
(_dl_lookup_symbol_skip): Likewise.
(_dl_lookup_versioned_symbol): Likewise.
(_dl_lookup_versioned_symbol_skip): Likewise.
* elf/dl-open.c: Don't define _dl_load_lock here...
* elf/rtld.c: ...but here...
* elf/dl-support.c: ...and here.
* elf/dl-close.c (_dl_close): Close also dependent objects introduce
through relocation.
* elf/dl-fini.c (_dl_fini): Also take dependencies introduced through
relocations.
* dlfcn/Makefile (glrefmain.out): Test is not expected to fail
anymore.
* dlfcn/glrefmain.c: Add one more debug message.
* Makeconfig (preprocess-versions): Don't add $(CPPFLAGS) to compiler
command line.
* Makerules (sysd-versions): Use ( ) instead of { }.
* elf/dl-load.c: Use __builtin_expect to signal that compiler should
optimize for the non-debugging case.
* elf/dl-lookup.c: Likewise.
* sysdeps/generic/libc-start.c: Likewise.
* Makeconfig (preprocess-versions): New canned sequence for running
cpp on shlib-versions and the like.
(soversions.i): Use it.
* Makerules (Versions.all, sysd-versions): Use it to preprocess the
Versions.def and Versions files.
soversions.mk generation moved here; result is a canonicalized
list "LIB VERSION [SET]" for this configuration.
(soversions.mk): Use that as input. Don't emit map-firstversions.
* Makerules (version-renames.def): New target, generated from
soversions.i with contents that was in $(map-firstversions).
(Versions.all): Don't depend on soversions.mk, depend on
version-renames.def instead; just cat it into the input.
supported version for libc 0.2.90.libio to GLIBC_2.2.
* Makeconfig (soversions.mk): Grok new third column in shlib-versions,
and use it to emit new variable `map-firstversions'.
* scripts/firstversions.awk: New file.
* Makerules (Versions.all): Use scripts/firstversions.awk and
the $(map-firstversions) value to generate a modified versions list
that includes renames in "A = B" syntax for each version set earlier
than the "earliest symbol version" named in shlib-versions.
* scripts/versions.awk: Recognize "A = B" lines in the input to mean
rename version set A to B in the output to the intermediate file.
* scripts/abi-versions.awk: New file.
* Makerules (abi-versions.h): New target, generated by that script.
[$(versioning) = yes] (before-compile): Prepend abi-versions.h.
* include/shlib-compat.h: New file, uses that generated header.
after stripping # comments, and then run it through cpp.
This allows things like "%ifdef FOO" based on config.h settings.
* shlib-versions [USE_IN_LIBIO] (.*-.*-gnu-gnu*): libc=0.2.90.libio
Roland McGrath
Ulrich Drepper
Andreas Jaeger
Greg McGary