an old fstatat bug

[Bruno Haible]

On a glibc 2.7 system, a recent m4 tarball fails its tests, due to this:

FAIL: test-fstatat
==================

../../tests/test-stat.h:49: assertion 'func ("", &st1) == -1' failed
FAIL test-fstatat (exit status: 134)

So, apparently, fstatat(_, "", _) succeeds instead of failing. fstatat
is implemented as an inline function in the system headers.

I don't think it's worth a workaround, as it's fixed in newer distros
for many years already.


2021-05-13  Bruno Haible  <bruno@clisp.org>

        fstatat: Document a glibc 2.7 bug.
        * doc/posix-functions/fstatat.texi: Document an old glibc 2.7 bug.

diff --git a/doc/posix-functions/fstatat.texi b/doc/posix-functions/fstatat.texi
index b75f421..dee0330 100644
--- a/doc/posix-functions/fstatat.texi
+++ b/doc/posix-functions/fstatat.texi
@@ -35,5 +35,9 @@ offset from @code{tv_sec}.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+This function does not fail when the second argument is an empty string
+on some platforms:
+glibc 2.7.
+@item
 @xref{sys/stat.h}, for general portability problems with @code{struct stat}.
 @end itemize