diff --git a/src/plugins/projectexplorer/debugginghelper.cpp b/src/plugins/projectexplorer/debugginghelper.cpp
index de4c5abb095ab344049e28219dd58a25db4d69f9..05c4aab59a5e7d2b731b7b81f0129155973522b6 100644
--- a/src/plugins/projectexplorer/debugginghelper.cpp
+++ b/src/plugins/projectexplorer/debugginghelper.cpp
@@ -132,7 +132,7 @@ QString DebuggingHelperLibrary::buildDebuggingHelperLibrary(const QString &qmake
     const QString directory = copyDebuggingHelperLibrary(qtInstallDataDir(qmakePath), &errorMessage);
     if (directory.isEmpty())
         return errorMessage;
-    return buildDebuggingHelperLibrary(directory, make, qmakePath, QString::null, env);
+    return buildDebuggingHelperLibrary(directory, make, qmakePath, env);
 }
 
 // Copy helper source files to a target directory, replacing older files.
@@ -188,7 +188,7 @@ QString DebuggingHelperLibrary::copyDebuggingHelperLibrary(const QString &qtInst
     return QString();
 }
 
-QString DebuggingHelperLibrary::buildDebuggingHelperLibrary(const QString &directory, const QString &makeCommand, const QString &qmakeCommand, const QString &mkspec, const Environment &env)
+QString DebuggingHelperLibrary::buildDebuggingHelperLibrary(const QString &directory, const QString &makeCommand, const QString &qmakeCommand, const Environment &env)
 {
     QString output;
     const QChar newline = QLatin1Char('\n');
@@ -218,7 +218,7 @@ QString DebuggingHelperLibrary::buildDebuggingHelperLibrary(const QString &direc
     output += QCoreApplication::translate("ProjectExplorer::DebuggingHelperLibrary", "Running %1 ...\n").arg(qmakeCommand);
 
     QStringList makeArgs;
-    makeArgs << QLatin1String("-spec")<< (mkspec.isEmpty() ? QString(QLatin1String("default")) : mkspec) << QLatin1String("gdbmacros.pro");
+    makeArgs << QLatin1String("-spec")<< QString(QLatin1String("default")) << QLatin1String("gdbmacros.pro");
     proc.start(qmakeCommand, makeArgs);
     proc.waitForFinished();
 
diff --git a/src/plugins/projectexplorer/debugginghelper.h b/src/plugins/projectexplorer/debugginghelper.h
index a9f05f537647815a0cb917d4d7874050fc235c48..0fda605a98446527e515edc5db5a445856c22eec 100644
--- a/src/plugins/projectexplorer/debugginghelper.h
+++ b/src/plugins/projectexplorer/debugginghelper.h
@@ -53,7 +53,7 @@ public:
 
     // Build the helpers and return the output log/errormessage.
     static QString buildDebuggingHelperLibrary(const QString &qmakePath, const QString &make, const Environment &env);
-    static QString buildDebuggingHelperLibrary(const QString &directory, const QString &makeCommand, const QString &qmakeCommand, const QString &mkspec, const Environment &env);
+    static QString buildDebuggingHelperLibrary(const QString &directory, const QString &makeCommand, const QString &qmakeCommand, const Environment &env);
 
     // Copy the source files to a target location and return the chosen target location.
     static QString copyDebuggingHelperLibrary(const QString &qtInstallData, QString *errorMessage);
diff --git a/src/plugins/qt4projectmanager/qtversionmanager.cpp b/src/plugins/qt4projectmanager/qtversionmanager.cpp
index ee1b0c36f6f3c05a11c7f6596d8f62d8a74ea1d7..4e3cc684319b1d57e73743a846e35d1016bb4ce7 100644
--- a/src/plugins/qt4projectmanager/qtversionmanager.cpp
+++ b/src/plugins/qt4projectmanager/qtversionmanager.cpp
@@ -1410,7 +1410,7 @@ QString QtVersion::buildDebuggingHelperLibrary()
     QString output;
     QString directory = DebuggingHelperLibrary::copyDebuggingHelperLibrary(qtInstallData, &output);
     if (!directory.isEmpty())
-        output += DebuggingHelperLibrary::buildDebuggingHelperLibrary(directory, tc->makeCommand(), qmakeCommand(), mkspec(), env);
+        output += DebuggingHelperLibrary::buildDebuggingHelperLibrary(directory, tc->makeCommand(), qmakeCommand(), env);
     m_hasDebuggingHelper = !debuggingHelperLibrary().isEmpty();
     delete tc;
     return output;