while(1); -> while (1) asm ("WFI");

Saves power and prevents heating

teensy4/startup.c

 #else
 	if ( F_CPU_ACTUAL >= 600000000 )
 		set_arm_clock(100000000);
-	while (1) {
-	}
+	while (1) asm ("WFI");
 #endif
 }
 
 __attribute__((weak))
 void _exit(int status)
 {
-	while (1);
+	while (1) asm ("WFI");
 }
 
 __attribute__((weak))
 void __cxa_pure_virtual()
 {
-	while (1);
+	while (1) asm ("WFI");
 }
 
 __attribute__((weak))
 __attribute__((weak))
 void abort(void)
 {
-	while (1) ;
+	while (1) asm ("WFI");
 }