2 files changed, 7 insertions, 0 deletions
diff --git a/qmake/project.cpp b/qmake/project.cpp
index 2be68be..9cf6a6f 100644
--- a/qmake/project.cpp
+++ b/qmake/project.cpp
@@ -671,6 +671,7 @@ QMakeProject::reset()
     scope_blocks.push(ScopeBlock());
     iterator = 0;
     function = 0;
+    backslashWarned = false;
 }
 
 bool
@@ -2933,6 +2934,11 @@ QMakeProject::doVariableReplaceExpand(const QString &str, QMap<QString, QStringL
                     break;
                 }
             }
+            if(!escape && !backslashWarned) {
+                backslashWarned = true;
+                warn_msg(WarnDeprecated, "%s:%d: Unescaped backslashes are deprecated.",
+                         parser.file.toLatin1().constData(), parser.line_no);
+            }
             if(escape || !replaced)
                 unicode =0;
         } else if(!quote && (unicode == SINGLEQUOTE || unicode == DOUBLEQUOTE)) {
diff --git a/qmake/project.h b/qmake/project.h
index 0c542db..fd8ced1 100644
--- a/qmake/project.h
+++ b/qmake/project.h
@@ -80,6 +80,7 @@ class QMakeProject
 
     bool recursive;
     bool own_prop;
+    bool backslashWarned;
     QString pfile, cfile;
     QMakeProperty *prop;
     void reset();