log a warning message if File#setLastModified fails. PR 49485

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@957442 13f79535-47bb-0310-9956-ffa450edef68

WHATSNEW

@@ -112,6 +112,11 @@ Other changes:
    scenarios where a given extension-point may or may not exist.
    Bugzilla Report 49473.   
 
+ * Ant now logs a warning message if it fails to change the file
+   modification time in for example when using <touch> or preserving
+   timestamps in various tasks.
+   Bugzilla Report 49485.
+
 Changes from Ant 1.8.0 TO Ant 1.8.1 
 ===================================
 

src/main/org/apache/tools/ant/types/resources/FileResource.java

@@ -345,7 +345,9 @@ public class FileResource extends Resource implements Touchable, FileProvider,
             ((FileResource) getCheckedRef()).touch(modTime);
             return;
         }
-        getNotNullFile().setLastModified(modTime);
+        if (!getNotNullFile().setLastModified(modTime)) {
+            log("Failed to change file modification time", Project.MSG_WARN);
+        }
     }
 
     /**