diff --git a/lib/cocoapods/installer/xcode/pods_project_generator/pod_target_installer.rb b/lib/cocoapods/installer/xcode/pods_project_generator/pod_target_installer.rb
index c21eb8c9a7..7d60ce3359 100644
--- a/lib/cocoapods/installer/xcode/pods_project_generator/pod_target_installer.rb
+++ b/lib/cocoapods/installer/xcode/pods_project_generator/pod_target_installer.rb
@@ -1059,7 +1059,7 @@ def add_header(file_accessor, build_file, public_headers, project_headers, priva
 
             if target.build_as_framework? && !header_mappings_dir(file_accessor).nil? && acl != 'Project'
               relative_path = if mapping_dir = header_mappings_dir(file_accessor)
-                                file_ref.real_path.relative_path_from(mapping_dir)
+                                file_ref.real_path.relative_path_from(Pathname.new(mapping_dir).realpath)
                               else
                                 file_ref.real_path.relative_path_from(file_accessor.path_list.root)
                               end