* lib/realloc.c (rpl_realloc): Simplify and tune by using
HAVE_REALLOC_0_NONNULL and HAVE_MALLOC_PTRDIFF, and
by having just one call to realloc instead of two.
* lib/reallocarray.c (reallocarray): Simplify and tune
by delegating the zero case to the revised realloc.
* m4/eealloc.m4 (_AC_FUNC_REALLOC_IF): Since only eealloc uses
this macro now, move its definition here ...
* m4/realloc.m4: ... from here.
(gl_FUNC_REALLOC_0_NONNULL): Also check that realloc (p, 0)
returns nonnull. Require gl_FUNC_REALLOC_POSIX.
Define HAVE_REALLOC_0_NONNULL.
* m4/reallocarray.m4 (gl_FUNC_REALLOCARRAY):
Also replace reallocarray if it returns a null pointer for size zero.
* modules/eealloc (Files): Remove m4/realloc.m4.
* modules/realloc-posix (Depends-on): Add extensions-aix.
* modules/reallocarray (Files): Add m4/realloc.m4.
* lib/reallocarray.c (reallocarray): Use simpler workaround
for realloc glitch, which does not involve malloc.
* modules/reallocarray (Depends-on): Remove malloc-posix.
stdckdint.h is part of draft C23 and therefore is more likely
to be familiar to programmers in the future, so prefer it to
intprops.h in files that don’t need non-_WRAPV intprops.h macros.
* lib/alignalloc.c, lib/backupfile.c, lib/fnmatch.c, lib/fnmatch_loop.c:
* lib/group-member.c, lib/malloca.c, lib/posixtm.c, lib/reallocarray.c:
* lib/xmalloc.c:
For files that can use stdckdint.h just as easily as intprops.h,
include the former instead of the latter, and use the former’s
ckd_* macros instead of the latter’s *_WRAPV macros.
* modules/alignalloc, modules/backup-rename, modules/backupfile:
* modules/fnmatch, modules/group-member, modules/malloca:
* modules/posixtm, modules/reallocarray:
* modules/relocatable-prog-wrapper, modules/xalloc:
Depend on stdckdint instead of intprops.
* lib/reallocarray.c: Include intprops.h.
(reallocarray): Use INT_MULTIPLY_WRAPV instead of
xalloc_oversized, as it now suffices and is likely a bit more
efficient (five fewer machine insns on Ubuntu 20.10 x86-64).
* modules/reallocarray (Depends-on): Depend on intprops, not
xalloc-oversized. Use conditional dependencies to avoid building
realloc-gnu when not needed.
reallocarray is a new function in glibc 2.26 to safely allocate an array
of memory locations with integer overflow protection.
* MODULES.html.sh: Add reallocarray.
* doc/glibc-functions/reallocarray.texi: Documentation for reallocarray.
* lib/reallocarray.c: New file to implement module reallocarray.
* lib/stdlib.in.h: Add function declarations for reallocarray.
* m4/reallocarray.m4: New file.
* m4/stdlib_h.m4: Declare reallocarray.
* modules/reallocarray: New file.
* modules/reallocarray-test: New file.
* modules/stdlib: Coerce stdlib.h to export reallocarray.
* tests/test-reallocarray.c: New test.
Collin Funk