should compile for all boards

DCCEXParser.cpp

@@ -17,10 +17,10 @@
  *  You should have received a copy of the GNU General Public License
  *  along with CommandStation.  If not, see <https://www.gnu.org/licenses/>.
  */
+#include "DCC.h" // includes "Motordriver.h" and <Arduino.h>
 #include "defines.h"
 #include "StringFormatter.h"
 #include "DCCEXParser.h"
-#include "DCC.h"
 #include "DCCWaveform.h"
 #include "Turnouts.h"
 #include "Outputs.h"

DCCTimer.h

@@ -37,5 +37,14 @@ class DCCTimer {
   private:
 };
 
+#if defined(ARDUINO_ARCH_ESP32)
 extern portMUX_TYPE timerMux;
 #endif
+
+#if !(defined(ARDUINO_ARCH_ESP32) || defined(ARDUINO_ARCH_ESP8266))
+#ifndef IRAM_ATTR
+#define IRAM_ATTR
+#endif
+#endif
+
+#endif //DCCTimer.h

DCCWaveform.cpp

@@ -17,7 +17,7 @@
  *  You should have received a copy of the GNU General Public License
  *  along with CommandStation.  If not, see <https://www.gnu.org/licenses/>.
  */
- #pragma GCC optimize ("-O3")
+#pragma GCC optimize ("-O3")
 #include <Arduino.h>
 
 #include "defines.h"