diff --git a/autotests/libs/testrunner/shellscript.cpp b/autotests/libs/testrunner/shellscript.cpp
--- a/autotests/libs/testrunner/shellscript.cpp
+++ b/autotests/libs/testrunner/shellscript.cpp
@@ -35,7 +35,7 @@
         const auto tmpl = QStringLiteral("$env:_old_%1=$env:%1\r\n"
                                          "$env:%1=\"%2\"\r\n");
 #else
-        const auto tmpl = QStringLiteral("$_old_%1=$%1\n"
+        const auto tmpl = QStringLiteral("_old_%1=$%1\n"
                                          "%1=\"%2\"\n"
                                          "export %1\n");
 #endif