All the cool platforms support CLASH_DETECTION...

* configure.ac (CLASH_DETECTION): Define unconditionally.
Every platform using configure supports it.

* src/s/aix4-2.h, src/s/bsd-common.h, src/s/cygwin.h, src/s/darwin.h:
* src/s/gnu-linux.h, src/s/hpux10-20.h, src/s/template.h:
* src/s/usg5-4-common.h: Move CLASH_DETECTION to configure.

* etc/PROBLEMS: Recommend customizing create-lockfiles rather than
recompiling with CLASH_DETECTION unset.

9 files changed, 4 insertions, 34 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 0dc0f010066..c9e4cbbabc0 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,9 @@
 2012-07-11  Glenn Morris  <rgm@gnu.org>
 
+	* s/aix4-2.h, s/bsd-common.h, s/cygwin.h, s/darwin.h:
+	* s/gnu-linux.h, s/hpux10-20.h, s/template.h, s/usg5-4-common.h:
+	Move CLASH_DETECTION to configure.
+
 	* s/gnu.h: Remove file, which is now empty.
 
 	* s/gnu.h, s/gnu-linux.h:
diff --git a/src/s/aix4-2.h b/src/s/aix4-2.h
index b7bdc8739a7..5741ef7c492 100644
--- a/src/s/aix4-2.h
+++ b/src/s/aix4-2.h
@@ -42,7 +42,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 /* Perry Smith <pedz@ddivt1.austin.ibm.com> says these are correct.  */
 #define SIGNALS_VIA_CHARACTERS
-#define CLASH_DETECTION
 
 /* Perry Smith <pedz@ddivt1.austin.ibm.com> says these are correct.  */
 #undef sigmask
diff --git a/src/s/bsd-common.h b/src/s/bsd-common.h
index 98391740653..c9c531b70b6 100644
--- a/src/s/bsd-common.h
+++ b/src/s/bsd-common.h
@@ -60,10 +60,5 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 /* Define HAVE_SOCKETS if system supports 4.2-compatible sockets.  */
 #define HAVE_SOCKETS
 
-/* Define CLASH_DETECTION if you want lock files to be written
-   so that Emacs can tell instantly when you try to modify
-   a file that someone else has modified in his Emacs.  */
-#define CLASH_DETECTION
-
 /* Send signals to subprocesses by "typing" special chars at them.  */
 #define SIGNALS_VIA_CHARACTERS
diff --git a/src/s/cygwin.h b/src/s/cygwin.h
index 0bbdab0cca1..9faaea785d7 100644
--- a/src/s/cygwin.h
+++ b/src/s/cygwin.h
@@ -59,11 +59,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
     }							\
   while (0)
 
-/* Define CLASH_DETECTION if you want lock files to be written
-   so that Emacs can tell instantly when you try to modify
-   a file that someone else has modified in his Emacs.  */
-#define CLASH_DETECTION
-
 /* If the system's imake configuration file defines `NeedWidePrototypes'
    as `NO', we must define NARROWPROTO manually.  Such a define is
    generated in the Makefile generated by `xmkmf'.  If we don't
diff --git a/src/s/darwin.h b/src/s/darwin.h
index 9371afee5e8..485fadbcb1f 100644
--- a/src/s/darwin.h
+++ b/src/s/darwin.h
@@ -83,11 +83,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
    for process-connection-type dependent on the kernel version.  */
 #define MIN_PTY_KERNEL_VERSION '7'
 
-/* Define CLASH_DETECTION if you want lock files to be written
-   so that Emacs can tell instantly when you try to modify
-   a file that someone else has modified in his Emacs.  */
-#define CLASH_DETECTION
-
 /* Avoid the use of the name init_process (process.c) because it is
    also the name of a Mach system call.  */
 #define init_process emacs_init_process
diff --git a/src/s/gnu-linux.h b/src/s/gnu-linux.h
index 9f8a994bb7e..d61d3ae5621 100644
--- a/src/s/gnu-linux.h
+++ b/src/s/gnu-linux.h
@@ -80,11 +80,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #define HAVE_SOCKETS
 
-/* Define CLASH_DETECTION if you want lock files to be written
-   so that Emacs can tell instantly when you try to modify
-   a file that someone else has modified in his Emacs.  */
-#define CLASH_DETECTION
-
 /* Here, on a separate page, add any special hacks needed
    to make Emacs work on this system.  For example,
    you might define certain system call names that don't
diff --git a/src/s/hpux10-20.h b/src/s/hpux10-20.h
index 7d8222761b3..ca8bcecb1f9 100644
--- a/src/s/hpux10-20.h
+++ b/src/s/hpux10-20.h
@@ -36,11 +36,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 /* Define HAVE_SOCKETS if system supports 4.2-compatible sockets.  */
 #define HAVE_SOCKETS
 
-/* Define CLASH_DETECTION if you want lock files to be written
-   so that Emacs can tell instantly when you try to modify
-   a file that someone else has modified in his Emacs.  */
-#define CLASH_DETECTION
-
 /* Special hacks needed to make Emacs run on this system.  */
 
 /* This is how to get the device name of the tty end of a pty.  */
diff --git a/src/s/template.h b/src/s/template.h
index 17c003a8df5..83027dc591b 100644
--- a/src/s/template.h
+++ b/src/s/template.h
@@ -66,11 +66,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 /* #undef subprocesses */
 
-/* Define CLASH_DETECTION if you want lock files to be written
-   so that Emacs can tell instantly when you try to modify
-   a file that someone else has modified in his Emacs.  */
-#define CLASH_DETECTION
-
 /* If the character used to separate elements of the executable path
    is not ':', #define this to be the appropriate character constant.  */
 /* #define SEPCHAR ':' */
diff --git a/src/s/usg5-4-common.h b/src/s/usg5-4-common.h
index 2676e9e5943..74f8908c8f9 100644
--- a/src/s/usg5-4-common.h
+++ b/src/s/usg5-4-common.h
@@ -51,9 +51,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
    constant to dimension an array.  So wire in the appropriate value here.  */
 #define NSIG_MINIMUM 32
 
-/* We can support this.  */
-#define CLASH_DETECTION
-
 /* Define HAVE_PTYS if the system supports pty devices.  */
 #define HAVE_PTYS