variadic-functions

I have a problem with using va_list. The below code works for an int: main() { int f1=1; float** m = function(n,f1); } float** function(int n,...) { va_list mem_list; va_start(mem_list, n); for (int i=0;i<n;i++) { for (int j=0;j<n;j++) { //m[i][j]=va_arg(mem_list,float); int f = va_arg(mem_list,int); printf("%i \n",f); } } va_end(mem_list); return NULL; } However when I change to a float i.e. float f1=1.0; float f = va_arg(mem_list,float); printf("%f \n",f); It does not return the right value (the value is 0.00000). I am extremely confused at what is happening. In the context of a varargs call

This is a weird question, but is there a standard way to manipulate the contents of a va_list before passing it to another function? For instance, suppose I have two functions, sum and vsum : int vsum(int n, va_list ap) { int total = 0; for (int i = 0; i < n; ++i) { total += va_arg(n, int); return total; } int sum(int n, ...) { va_list ap; va_start(ap, n); int total = vsum(n, ap); va_end(ap); return total; } If I call sum as sum(4, 1, 2, 3, 4) , I expect to get the result 10. Now let's suppose that instead of calling vsum directly, sum calls an intermediate function, vsum_stub which does the

My code contains snippets like these: std::va_list ap; va_start(ap, msgfmt); snprintf_buf buf; const tchar * msg = buf.print_va_list(msgfmt, ap); va_end(ap); These are short and va_start() and va_end() are close together so they are not much of a problem. Exceptions from calls in between the two could be a problem (or not?). Simple test shows that calling va_start() from a function without ellipsis is not allowed. Is calling va_end() from a different function than va_start() was called from allowed or not? Basically, I am curious if it is possible to use the SBRM/RAII idiom for these calls,