diff --git a/ide/debugmanager.pas b/ide/debugmanager.pas
index 71741a0006..aad9b3a35e 100644
--- a/ide/debugmanager.pas
+++ b/ide/debugmanager.pas
@@ -1138,6 +1138,9 @@ begin
   Result:=False;
   if Destroying then exit;
 
+  // some debuggers (e.g. gdb) sometimes returns linux path delims under windows
+  // => fix that
+  Filename := TrimFilename(SwitchPathDelims(Filename,pdsSystem));
   SrcFile := Filename;
   SrcFile := MainIDE.FindSourceFile(SrcFile,Project1.ProjectDirectory,
                       [fsfSearchForProject,fsfUseIncludePaths,fsfUseDebugPath]);