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author | 2018-02-05 14:13:41 -0500 | |
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committer | 2018-02-07 10:10:32 -0500 | |
commit | 63fb8f9aa9d19f85599afe4b849b567aefd70a36 (patch) | |
tree | 607f89b682d7c7200b389cba7de7e4496806565f /csu | |
parent | Post-cleanup 1: move libio.h back out of bits/. (diff) | |
download | glibc-63fb8f9aa9d19f85599afe4b849b567aefd70a36.tar.gz glibc-63fb8f9aa9d19f85599afe4b849b567aefd70a36.tar.bz2 glibc-63fb8f9aa9d19f85599afe4b849b567aefd70a36.zip |
Post-cleanup 2: minimize _G_config.h.
Nearly everything in _G_config.h is either junk or more appropriately
defined elsewhere:
* _G_fpos_t, _G_fpos64_t, and _G_BUFSIZ are already completely unused.
* All remaining uses of _G_va_list have been changed to __gnuc_va_list.
* The definition of _G_HAVE_ST_BLKSIZE/_IO_HAVE_ST_BLKSIZE has
been inlined into its sole use.
* The complete definition of _G_iconv_t has been moved to libio.h and
renamed _IO_iconv_t (all actual users used that name).
* _G_IO_IO_FILE_VERSION is vestigial; some code cares whether
_IO_stdin_used exists, but nothing looks at its value. I've
preserved the value as a hardwired constant in csu/init.c.
This means csu/init.c no longer needs to include anything.
* Many of the headers included by _G_config.h were already being
included directly by either either libio.h or stdio.h; the
remaining ones were moved to libio.h.
* _G_HAVE_MREMAP is still relevant, because mremap genuinely is a
Linux extension; it's not in POSIX and as far as I can tell it's
not available on the Hurd either. I also preserved _G_HAVE_MMAP,
since it's conceivable someone would want to port glibc to a
MMU-less, mmap-less environment in the future. Both are now always
defined to 1/0 as is the current convention, instead of the older
1/undef convention. These are the only symbols still defined in
_G_config.h.
* The actual inclusion of _G_config.h moves from libio.h to libioP.h,
as this is where a potential override of _G_HAVE_MMAP happens.
* The #ifdef logic in libioP.h controlling _IO_JUMPS_OFFSET has been
simplified.
After this patch, the only surviving _G_ symbols are the struct tag
names _G_fpos_t and _G_fpos64_t, which are preserved for the sake of
C++ mangled names in applications, and _G_HAVE_MMAP and _G_HAVE_MREMAP,
which do not seem worth renaming.
Installed stripped libraries are unchanged by this patch.
* bits/_G_config.h: Move back to sysdeps/generic/_G_config.h.
Delete all contents except for definitions of _G_HAVE_MMAP and
_G_HAVE_MREMAP. Add commentary explaining those two symbols.
* sysdeps/unix/sysv/linux/bits/_G_config.h: Move back to
sysdeps/unix/sysv/linux/_G_config.h. Make same content
change as above.
* libio/libio.h: Don't include bits/_G_config.h here.
Include stddef.h with __need_wchar_t defined. Include
bits/types/__mbstate_t.h, bits/types/wint_t.h, and gconv.h.
Define _IO_iconv_t here, directly.
Don't define _IO_HAVE_ST_BLKSIZE.
* libio/libioP.h: Include _G_config.h here. Move include of
shlib-compat.h up with rest of includes. Simplify conditionals
controlling definition of _IO_JUMPS_OFFSET.
* csu/init.c: Remove always-true #if around entire file.
Don't include stdio.h. Set _IO_stdin_used to hardwired
constant 0x20001, and update commentary.
* include/stdio.h, sysdeps/ieee754/ldbl-opt/nldbl-compat.h:
Replace all uses of _G_va_list with __gnuc_va_list.
* libio/filedoalloc.c: Use #if defined _STATBUF_ST_BLKSIZE
instead of #if _IO_HAVE_ST_BLKSIZE.
* libio/fileops.c: Test _G_HAVE_MREMAP with #if, not #ifdef.
* libio/iofdopen.c, libio/iofopen.c: Test _G_HAVE_MMAP with #if,
not #ifdef.
Diffstat (limited to 'csu')
-rw-r--r-- | csu/init.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/csu/init.c b/csu/init.c index 178063b44b..c2f978f3da 100644 --- a/csu/init.c +++ b/csu/init.c @@ -16,11 +16,8 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ -#if defined __GNUC__ && __GNUC__ >= 2 - -#include <stdio.h> - -/* This records which stdio is linked against in the application. */ -const int _IO_stdin_used = _G_IO_IO_FILE_VERSION; - -#endif +/* Vestigial libio version number. Some code in libio checks whether + this symbol exists in the executable, but nothing looks at its + value anymore; the value it was historically set to has been + preserved out of an abundance of caution. */ +const int _IO_stdin_used = 0x20001; |