The result of this macro is cached in the
@code{ac_cv_func_malloc_0_nonnull} variable.
+The result might contain spaces, e.g., @code{guessing yes}.
If you don't want to maintain a @code{malloc.c} file in your package
manually, you can instead use the Gnulib module @code{malloc-gnu}.
The result of this macro is cached in the
@code{ac_cv_func_realloc_0_nonnull} variable.
+The result might contain spaces, e.g., @code{guessing yes}.
This macro does not check compatibility with glibc @code{realloc (@var{p}, 0)}
when @var{p} is non-null, as glibc 1--2.1 behaves differently from glibc