Re: AC_FUNC_MMAP lacks <unistd.h> include?

[Paul Eggert]

On 5/11/23 07:08, Zack Weinberg wrote:
> Unless someone
> knows of a bug in some old kernel where the first*disk block*  of an oversized
> mmap would be properly zeroed and then the rest of it would be memory garbage

Yes, that was the reason I went back to configuring a getpagesize 
substitute: I wanted the test to continue to check for that 
improperly-zeroed bug (a check that I didn't notice in my earlier commit).

Although the original motivation for the improperly-zeroed test is old 
GNU grep, GNU grep no longer uses mmap. However, perhaps some other 
package now cares about this behavior, so it's probably better to keep 
testing for it.