Fix compiler warnings

teensy4/analog.c

 
 void analogReadAveraging(unsigned int num)
 {
-  uint32_t tmp32, mode, avg=0;
+  uint32_t tmp32, mode;
   
   //disable averaging
   tmp32 = ADC1_GC;

teensy4/startup.c

 void configure_cache(void);
 void unused_interrupt_vector(void);
 void usb_pll_start();
-extern void analog_init(void);
-extern void pwm_init(void);
-uint32_t set_arm_clock(uint32_t frequency);
+extern void analog_init(void); // analog.c
+extern void pwm_init(void); // pwm.c
+uint32_t set_arm_clock(uint32_t frequency); // clockspeed.c
+extern void __libc_init_array(void); // C++ standard library
 
 
 __attribute__((section(".startup"), optimize("no-tree-loop-distribute-patterns")))
 	set_arm_clock(600000000);
 	//set_arm_clock(984000000); Ludicrous Speed
 
-	uint32_t armpll = CCM_ANALOG_PLL_ARM;
-	uint32_t armdiv = CCM_CACRR;
-	uint32_t cbcdr = CCM_CBCDR;
-	uint32_t cbcmr = CCM_CBCMR;
-
-	printf("ARM PLL = %u MHz\n", (armpll & 0x7F) * 12);
-	printf("ARM divisor = %u\n", armdiv + 1);
-	printf("AHB divisor = %u\n", ((cbcdr >> 10) & 7) + 1);
-	printf("IPG divisor = %u\n", ((cbcdr >> 8) & 3) + 1);
-
 	while (millis() < 20) ; // wait at least 20ms before starting USB
 	usb_init();
 	analog_init();

teensy4/usb.c

 #define USB_DESC_LIST_DEFINE
 #include "usb_desc.h"
 #include "usb_serial.h"
+#include "core_pins.h" // for delay()
 #include <string.h>
 #include "debug/printf.h"
 
 		//printf("USBPHY1_RX=%08lX\n", USBPHY1_RX);
 		//printf("USBPHY1_CTRL=%08lX\n", USBPHY1_CTRL);
 		//printf("USB1_USBMODE=%08lX\n", USB1_USBMODE);
-		delay(100);
+		delay(25);
 	}
 #endif
 	// Device Controller Initialization, page 3161

teensy4/usb_serial.c

 }
 
 
-static transfer_t volatile transfer __attribute__ ((used, aligned(32)));
+static transfer_t transfer __attribute__ ((used, aligned(32)));
 static uint8_t txbuffer[1024];
 //static uint8_t txbuffer1[1024];
 //static uint8_t txbuffer2[1024];
 	int count=0;
 	//digitalWriteFast(13, HIGH);
 	while (1) {
-		uint32_t status = (volatile)(transfer.status);
+		uint32_t status = transfer.status;
 		if (count > 10) printf("status = %x\n", status);
 		if (!(status & 0x80)) break;
 		count++;