Also, switch from eealloc.m4 to malloc.m4 to determine
whether malloc (0) returns nonnull.
* lib/malloca.c (mmalloca): Use HAVE_MALLOC_0_NONNULL,
not MALLOC_0_IS_NONNULL.
* m4/malloca.m4 (gl_MALLOCA): Require gl_FUNC_MALLOC_GNU,
not gl_EEMALLOC.
* modules/malloca (Files): Remove m4/eemalloc.m4.
(Depends-on): Add extensions-aix.
* modules/relocatable-prog-wrapper:
AC_REQUIRE gl_FUNC_MALLOC_POSIX to suppress Autoconf 2.71
“warning: AC_REQUIRE: `gl_FUNC_MALLOC_POSIX' was expanded before
it was required”.