Code that compiles with gcc but not with g++

Question

I am writing a program in c, but i need to use a c++ library to work with an ADC's.

In my code I have a library that I wrote called scheduler, this library compiles with no errors with gcc but when I try to compile with g++ I get the error:

scheduler.c:55:35: error: too many arguments to function call, expected 0, have 1
                    tasks[i].func(tasks[i].args);

Here is the scheduler struct:

typedef struct _tasks_t
{
    char *name;
    unsigned int period; /**< Contains the period the task. If it's 0 it doesn't execute the task */
    void (*func)();      /**< Contains a pointer to the function of the task */
    bool args_on;        /**< true if the function has arguments */
    void *args;          /**< pointer to function args */
} tasks_t;

And here are the lines that are generating the error:

    /** Goes through every task to check if the time passed is >= to the period and if the period is != 0 */
    for (i = 0; i < tasks_size; i++)
    {

        if ((time_ms - t_last[i] >= tasks[i].period) && (tasks[i].period != 0))
        {
            t_last[i] = time_ms; /** Saves the "new" last time that the task was executed */
            if (tasks[i].args_on)
            { /** Executes the task function */
                tasks[i].func(tasks[i].args);
            }
            else
            {
                tasks[i].func();
            }
        }
    }

[EDIT]: I solved the problem by writing void (*func)(void *) and now I pass function arguments in the for of an array or a struct.

Answer 1

void (*func)() is a function pointer to a function with unspecified arguments, when interpreted as C, but a function pointer to a function with 0 arguments, when interpreted as C++ (equivalent to void (*func)(void) in C).

tasks[i].func(tasks[i].args); calls it with one argument, which is invalid in C++.