west@calgary.UUCP (Darrin West) (04/14/88)
We have at&t c++ v1.1
I have a bit of a vague bug. This is due mainly to the size of
the program in which the bug is exhibiting itself (I have
spent many hours chopping out hunks of code in order
to narrow down the bug, with little success). Perhaps
someone else has run across it already, and will recognise
it.
I recently added a class v_time to a simulation library
I have been working on. It has a few contstructors, an
operator int and an assignment operator. This addition
causes a later call of a function to create
bad c code. (I know this because removing the
v_time declaration reverses the problem) The
function is much like a printf or exec call, where
the last eight parameters are char *'s, and have
default initializers of NULL.
Without the v_time code, a call of the function compiles
properly, initializing the last few arguments to zero.
With the code, c++ beleives the arguments should be
converted to type v_time, and generates c code to call
the v_time operator int. It just happens that that code
also takes the address of the constant 0, and thus does
not go through the c compiler.
When the function is not declared to have default initializers
the problem also does not occur.
Has anyone seen this happen before?
Any suggestions will be much appreciated (bug fixes will
elicit large amounts of praise and gratitude).
The following code (and a bunch more besides) generates the c code
that follows the /***********/
class v_time{
int t;
double dummy;
public:
v_time(){t=0;}
v_time(int i){t=i;}
operator int();//{return(t);} // this doesn't want to compile inline
int operator= (int i) { return(t = i);}
};
pid _create_req(char *type,char *group,char *name,char *a,
char *b,char *c,char *d,char *e,char *f,char *g,char *h);
pid new_st(char *group,char *name,char *a=0,char *b=0,char *c=0,
char *d=0,char *e=0,char *f=0,char *g=0,char *h=0)
{
return(_create_req("st",group,name,a,b,c,d,e,f,g,h));
}
/**************/
_auto_s = ( new_st ( & _auto__R7 , "m3", "st",
_v_time__OI ( (struct v_time *)(& 0 )) , _v_time__OI ( (struct
v_time *)(& 0 )) , _v_time__OI ( (struct v_time *)(& 0 )) ,
_v_time__OI ( (struct v_time *)(& 0 )) , _v_time__OI (
(struct v_time *)(& 0 )) , _v_time__OI ( (struct v_time *)(& 0 )) ,
_v_time__OI ( (struct v_time *)(& 0 )) ,
_v_time__OI ( (struct v_time *)(& 0 )) ) , _auto__R7 ) ;
Does this bug remain in v1.2?
What is the most recent version?
--
Darrin West, Newly MSc. ..![ubc-vision,ihnp4]!
Jade@Department of Computer Science alberta!calgary!west
University of Calgary. west@calgary.cdn
Brain fault (cortex dumped)