variadic functions - C++ method with variable arguments (...) reporting incorrect arg values -

i'm having trouble getting variable arguments pass method - method intended select random value within weighted distribution , return index of selected result.

an example usage be:

int pickuptype = randommanager->byweights( 3, 0.60f, 0.20f, 0.20f ); switch( pickuptype ) {     // ... pickuptype should 0 2, can branch on } 

the function defined follows:

#include <cstdarg>  int randommanager::byweights( int weightcount, ... ) {      va_list arglist;      // total of weights     va_start( arglist, weightcount );     float weighttotal = 0;     ( int = 0; < weightcount; i++ ) {         weighttotal += va_arg( arglist, float );     }     va_end( arglist );      // roll number in range     // ... (further processing - problem occurs above) } 

when run in debugger, call va_arg( arglist, float ) returning garbage values ( 2.0, 1.77499998, -1.08420217e-019 ), rather values passed in ( 0.60f, 0.20f, 0.20f ).

any ideas i'm doing wrong? far can tell i'm following spec exactly. i've been using http://www.cplusplus.com/reference/cstdarg/ reference.

in variadic function, float parameters converted doubles. try

weighttotal += va_arg( arglist, double );