Function pointer arguments ignored/not needed

I’m currently writing C code for a microprocessor and I came across something I couldn’t explain. I have implemented a command line interface using function pointers. To do this I have made a struct holding the name of the command, the pointer to the function to be run and also a help description.

typedef void(*command)(char *);
typedef struct commandStruct {
    char const *name;
    command execute;
    char const *help;
} commandStruct;

const commandStruct commands[] =
    {"led", CmdLed, "Turns on or off the LED1"},
    {"AT+START_SIM", start_simulation, "Starts the simulation"},
    {"AT+STOP_SIM", stop_simulation, "Stops the simulation"},
    {"",0,""} //End of table indicator.

void exec_command(char *buffer)
    uint16 i = 0;
    char *cmd = buffer;
    char *args;
    while (buffer[i])
        if(buffer[i] == '=')
            buffer[i] = 0;
            args = buffer + i + 1;

    uint16 cmdCount = 0;

void start_simulation(void) {run = 1;}
void stop_simulation(void) {run = 0;}
void CmdLed(char *args)
    P1DIR |= BIT0;
    if(!strcmp(args,"on")) P1OUT = 1;
    if(!strcmp(args,"off")) P1OUT = 0;

I have included above the function exec_command which is where the function pointer is used. At the bottom I have also put the start_simulation and stop_simulation functions, along with CmdLed. I wrote CmdLed at an earlier date and then came back and wrote start_simulation and stop_simulation. I had forgotten that I had defined my function pointer as taking a (char *) as an argument. However, I was surprised to find that everything still compiled and ran absolutely fine. Why is this? It seems that any arguments are just ‘dumped’ and not used.

Source: c#

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