* gcov-io.h: Add a local time stamp.

	(struct gcov_info): Add stamp field.
	(gcov_truncate): New.
	* coverage.c (read_counts_file): Skip the stamp.
	(coverage_begin_output): Write the stamp.
	(build_gcov_info): Declare and init the stamp.
	(coverage_finish): Only unlink data file, if stamp is zero.
	* gcov-dump.c (dump_file): Dump the stamp.
	* gcov.c (bbg_stamp): New.
	(release_structures): Clear bbg_stamp.
	(read_graph_file): Read stamp.
	(read_count_file): Check stamp.
	* libgcov.c (gcov_exit): Check stamp and truncate if needed.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@69006 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 13 insertions, 3 deletions

diff --git a/gcc/libgcov.c b/gcc/libgcov.c
index 74d830dc1b0..72126466f66 100644
--- a/gcc/libgcov.c
+++ b/gcc/libgcov.c
@@ -167,8 +167,10 @@ gcov_exit (void)
       gcov_unsigned_t tag, length;
       gcov_position_t summary_pos = 0;
 
-      /* Totals for this object file.  */
       memset (&this_object, 0, sizeof (this_object));
+      memset (&object, 0, sizeof (object));
+      
+      /* Totals for this object file.  */
       for (t_ix = c_ix = 0,
 	     ci_ptr = gi_ptr->counts, cs_ptr = this_object.ctrs;
 	   t_ix != GCOV_COUNTERS_SUMMABLE; t_ix++, cs_ptr++)
@@ -223,6 +225,15 @@ gcov_exit (void)
 	      gcov_version_mismatch (gi_ptr, length);
 	      goto read_fatal;
 	    }
+
+	  length = gcov_read_unsigned ();
+	  if (length != gi_ptr->stamp)
+	    {
+	      /* Read from a different compilation. Overwrite the
+		 file.  */
+	      gcov_truncate ();
+	      goto rewrite;
+	    }
 	  
 	  /* Merge execution counts for each function.  */
 	  for (f_ix = gi_ptr->n_functions, fi_ptr = gi_ptr->functions;
@@ -298,8 +309,6 @@ gcov_exit (void)
 	rewrite:;
 	  gcov_rewrite ();
 	}
-      else
-	memset (&object, 0, sizeof (object));
       if (!summary_pos)
 	memset (&program, 0, sizeof (program));
 
@@ -355,6 +364,7 @@ gcov_exit (void)
       
       /* Write out the data.  */
       gcov_write_tag_length (GCOV_DATA_MAGIC, GCOV_VERSION);
+      gcov_write_unsigned (gi_ptr->stamp);
       
       /* Write execution counts for each function.  */
       for (f_ix = gi_ptr->n_functions, fi_ptr = gi_ptr->functions; f_ix--;