2007-01-25 Richard Guenther <rguenther@suse.de>

	* doc/invoke.texi (-Wcoverage-mismatch): Document.
	* common.opt (-Wcoverage-mismatch): New warning option.
	* coverage.c (get_coverage_counts): Ignore coverage mismatch
	if -Wcoverage-mismatch is given.

	* gcc.dg/tree-prof/tree-prof.exp: Define _PROFILE_GENERATE
	and _PROFILE_USE.
	* gcc.dg/tree-prof/wcoverage-mismatch.c: New testcase.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@121169 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 36 insertions, 15 deletions

diff --git a/gcc/coverage.c b/gcc/coverage.c
index 399eb6ea6c6..ba9f1285fc2 100644
--- a/gcc/coverage.c
+++ b/gcc/coverage.c
@@ -347,25 +347,46 @@ get_coverage_counts (unsigned counter, unsigned expected,
     {
       warning (0, "no coverage for function %qs found", IDENTIFIER_POINTER
 	       (DECL_ASSEMBLER_NAME (current_function_decl)));
-      return 0;
+      return NULL;
     }
 
   checksum = compute_checksum ();
-  if (entry->checksum != checksum)
-    {
-      error ("coverage mismatch for function %qs while reading counter %qs",
-	     IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (current_function_decl)),
-	     ctr_names[counter]);
-      error ("checksum is %x instead of %x", entry->checksum, checksum);
-      return 0;
-    }
-  else if (entry->summary.num != expected)
+  if (entry->checksum != checksum
+      || entry->summary.num != expected)
     {
-      error ("coverage mismatch for function %qs while reading counter %qs",
-	     IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (current_function_decl)),
-	     ctr_names[counter]);
-      error ("number of counters is %d instead of %d", entry->summary.num, expected);
-      return 0;
+      static int warned = 0;
+      const char *id = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME
+			 (current_function_decl));
+
+      if (warn_coverage_mismatch)
+	warning (OPT_Wcoverage_mismatch, "coverage mismatch for function "
+		 "%qs while reading counter %qs", id, ctr_names[counter]);
+      else
+	error ("coverage mismatch for function %qs while reading counter %qs",
+	       id, ctr_names[counter]);
+
+      if (!inhibit_warnings)
+	{
+	  if (entry->checksum != checksum)
+	    inform ("checksum is %x instead of %x", entry->checksum, checksum);
+	  else
+	    inform ("number of counters is %d instead of %d",
+		    entry->summary.num, expected);
+	}
+
+      if (warn_coverage_mismatch
+	  && !inhibit_warnings
+	  && !warned++)
+	{
+	  inform ("coverage mismatch ignored due to -Wcoverage-mismatch");
+	  inform (flag_guess_branch_prob
+		  ? "execution counts estimated"
+		  : "execution counts assumed to be zero");
+	  if (!flag_guess_branch_prob)
+	    inform ("this can result in poorly optimized code");
+	}
+
+      return NULL;
     }
 
   if (summary)