Re: vsprintf float bug in GCC(?)

"Edward Byard" <ed@xxxxxxxxxxxxxxxxx> writes:

> Hi,
> 
> I'm having a BIG problem trying to vsprintf float values.
> Firstly I should mention that I am compiling for the H8/300 system using gcc
> version 2.7-91q1 (yes it's old - nothing I can do about that just yet).
> 
> I have a function called AlphaPrintf which prints to a 16-char long display,
> as such:
> 
> void AlphaPrintf(char *String, ...)
> {
>  char AlphaBuf[32];
>  va_list VarListPtr;
> 
>  va_start(VarListPtr,String);

What about va_end ? You must call va_end before you return from
    AlphaPrintf. (I know the gnu C lib doesn't require that, but other
    c libs do.)

>  vsprintf(AlphaBuf,String,VarListPtr);
> 
>  AlphaBuf[17] = '\0';
>  PrintOnDisplay(AlphaBuf);    /* will print until the null is reached (duh!)
> */
> }
> 
> I wish to be able to vsprintf a precision value (10.3f) , obtained from
> dividing a long int with a
> short int, cast to a double like so:
> 
> long int LongIntValue;
> short int ShortIntValue;
> 
> float FloatVar1 = LongIntValue/(double)ShortIntValue;
> 
> and I am passing AlphaPrintf this:
> 
> AlphaPrintf("%10.3f",FloatVar1);
> 
[snip]