Allow qmake to work even if toolchain libraries are not static

Task-number: QTCREATORBUG-6576

Change-Id: I49f458181a3ba0697a096b2a6435838fbcdbc759
Reviewed-by: Daniel Teske <daniel.teske@nokia.com>

src/plugins/qtsupport/baseqtversion.cpp

@@ -1184,7 +1184,18 @@ bool BaseQtVersion::queryQMakeVariables(const Utils::FileName &binary, QHash<QSt
         return false;
 
     QProcess process;
+    Utils::Environment env = Utils::Environment::systemEnvironment();
+
+#ifdef Q_OS_WIN
+    // Add tool chain environments. This is necessary for non-static qmakes e.g. using mingw on windows
+    QList<ProjectExplorer::ToolChain *> tcList = ProjectExplorer::ToolChainManager::instance()->toolChains();
+    foreach (ProjectExplorer::ToolChain *tc, tcList)
+        tc->addToEnvironment(env);
+#endif
+
+    process.setEnvironment(env.toStringList());
     process.start(qmake.absoluteFilePath(), QStringList(QLatin1String("-query")), QIODevice::ReadOnly);
+
     if (!process.waitForStarted()) {
         *qmakeIsExecutable = false;
         qWarning("Cannot start '%s': %s", qPrintable(binary.toUserOutput()), qPrintable(process.errorString()));