From: Paul Eggert <eggert@cs.ucla.edu>
Date: Tue, 4 Jul 2006 05:59:05 +0000 (+0000)
Subject: * cycle-check.h (CYCLE_CHECK_REFLECT_CHDIR_UP): Abort if this
X-Git-Tag: cvs-readonly~2271
X-Git-Url: http://erislabs.org.uk/gitweb/?a=commitdiff_plain;h=ed664fa4ea5bdee8952dbcdf614b87303b8f67a1;p=gnulib.git

* cycle-check.h (CYCLE_CHECK_REFLECT_CHDIR_UP): Abort if this
macro is used before the first cycle_check call.
---

diff --git a/lib/ChangeLog b/lib/ChangeLog
index 1fcee2afc..244118bbf 100644
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,8 @@
+2006-07-03  Jim Meyering  <jim@meyering.net>
+
+	* cycle-check.h (CYCLE_CHECK_REFLECT_CHDIR_UP): Abort if this
+	macro is used before the first cycle_check call.
+
 2006-07-03  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* stdint_.h: Include <sys/types.h> after @FULL_PATH_STDINT_H@, for
diff --git a/lib/cycle-check.h b/lib/cycle-check.h
index b137a60a8..927f3e51f 100644
--- a/lib/cycle-check.h
+++ b/lib/cycle-check.h
@@ -45,6 +45,9 @@ bool cycle_check (struct cycle_check_state *state, struct stat const *sb);
 # define CYCLE_CHECK_REFLECT_CHDIR_UP(State, SB_dir, SB_subdir)	\
   do								\
     {								\
+      /* You must call cycle_check at least once before using this macro.  */ \
+      if ((State)->chdir_counter == 0)				\
+        abort ();						\
       if (SAME_INODE ((State)->dev_ino, SB_subdir))		\
 	{							\
 	  (State)->dev_ino.st_dev = (SB_dir).st_dev;		\