[FYI] docs: "make distcheck" implementation details are not to be abused

[Stefano Lattarini]

* doc/automake.texi: State explicitly and in detail that the exact location
and the exact structure of the subdirectory used by "make distcheck" is to
be considered an implementation detail, which can change at any time.

Signed-off-by: Stefano Lattarini <address@hidden>
---
 doc/automake.texi | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/doc/automake.texi b/doc/automake.texi
index fb6c05f..383a811 100644
--- a/doc/automake.texi
+++ b/doc/automake.texi
@@ -1242,8 +1242,12 @@ uninstall} do not omit any file (@pxref{Standard 
Targets}),
 and it checks that @code{DESTDIR} installations work (@pxref{DESTDIR}).
 @end itemize
 
-All of these actions are performed in a temporary subdirectory, so
-that no root privileges are required.
+All of these actions are performed in a temporary directory, so that no
+root privileges are required.  Please note that the exact location and the
+exact structure of such a subdirectory (where the extracted sources are
+placed, how the temporary build and install directories are named and how
+deeply they are nested, etc.) is to be considered an implementation detail,
+which can change at any time; so do not rely on it.
 
 Releasing a package that fails @code{make distcheck} means that one of
 the scenarios we presented will not work and some users will be
@@ -8555,6 +8559,13 @@ finally, makes another tarball to ensure the 
distribution is
 self-contained.
 @end itemize
 
+All of these actions are performed in a temporary directory.  Please
+note that the exact location and the exact structure of such a directory
+(where the read-only sources are placed, how the temporary build and
+install directories are named and how deeply they are nested, etc.) is
+to be considered an implementation detail, which can change at any time;
+so do not reply on it.
+
 @vindex AM_DISTCHECK_CONFIGURE_FLAGS
 @vindex DISTCHECK_CONFIGURE_FLAGS
 @subheading DISTCHECK_CONFIGURE_FLAGS
-- 
2.1.3